Euler's fluid equations: Optimal Control vs Optimization
Darryl D. Holm
2009-09-28T23:59:59.000Z
An optimization method used in image-processing (metamorphosis) is found to imply Euler's equations for incompressible flow of an inviscid fluid, without requiring that the Lagrangian particle labels exactly follow the flow lines of the Eulerian velocity vector field. Thus, an optimal control problem and an optimization problem for incompressible ideal fluid flow both yield the \\emph {same} Euler fluid equations, although their Lagrangian parcel dynamics are \\emph{different}. This is a result of the \\emph{gauge freedom} in the definition of the fluid pressure for an incompressible flow, in combination with the symmetry of fluid dynamics under relabeling of their Lagrangian coordinates. Similar ideas are also illustrated for SO(N) rigid body motion.
Magnetically stimulated fluid flow patterns
Martin, Jim; Solis, Kyle
2014-08-06T23:59:59.000Z
Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.
Magnetically stimulated fluid flow patterns
Martin, Jim; Solis, Kyle
2014-03-06T23:59:59.000Z
Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.
Airfoil Shape Optimization for Transonic Flows of BetheZel'dovichThompson Fluids
Paris-Sud XI, Université de
of gasdynamics : 1 a @a @ s (1) where is the fluid density, a is the sound speed, and s is the entropy of thermodynamic conditions above the liquid/vapor coexistence curve, such that the fundamental derivative
McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.
1993-11-30T23:59:59.000Z
A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.
McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)
1993-01-01T23:59:59.000Z
A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.
Insertable fluid flow passage bridgepiece and method
Jones, Daniel O. (Glenville, NV)
2000-01-01T23:59:59.000Z
A fluid flow passage bridgepiece for insertion into an open-face fluid flow channel of a fluid flow plate is provided. The bridgepiece provides a sealed passage from a columnar fluid flow manifold to the flow channel, thereby preventing undesirable leakage into and out of the columnar fluid flow manifold. When deployed in the various fluid flow plates that are used in a Proton Exchange Membrane (PEM) fuel cell, bridgepieces of this invention prevent mixing of reactant gases, leakage of coolant or humidification water, and occlusion of the fluid flow channel by gasket material. The invention also provides a fluid flow plate assembly including an insertable bridgepiece, a fluid flow plate adapted for use with an insertable bridgepiece, and a method of manufacturing a fluid flow plate with an insertable fluid flow passage bridgepiece.
Osinski, Charles Anthony
1963-01-01T23:59:59.000Z
zero and unity. The Ostwald- de Waele Equation (4), commonly known as the power law, is sometimes used to describe fluid behavior of this type. The rheological equation is (4) where the parameters "k" and "n" are constant for a particular fluid... be extended to include Reynolds numbers and the type of flow determined to be laminar and/or turbulent. It is assumed that the transition from laminar to turbulent flow occurs at a Reynolds number of 2100, the numeric distribution of Reynolds numbers...
Fluid Gravity Engineering Rocket motor flow analysis
Anand, Mahesh
Fluid Gravity Engineering Capability · Rocket motor flow analysis -Internal (performance) -External (plume / contamination) · Effect on landing site (surface alteration) -In-depth flow through porous young scientists/engineers Fluid Gravity Engineering Ltd #12;
SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW
Santos, Juan
SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW J. E. Santos1, G. B. Savioli2, J. M. Carcione3, D´e, Argentina SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW p. #12;Introduction. I Storage of CO2). SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW p. #12;Introduction. II CO2 is separated from natural
Fluid Flow Simulation in Fractured Reservoirs
Sarkar, Sudipta
2002-01-01T23:59:59.000Z
The purpose of this study is to analyze fluid flow in fractured reservoirs. In most petroleum reservoirs, particularly carbonate reservoirs and some tight sands, natural fractures play a critical role in controlling fluid ...
Process for retarding fluid flow
Sandford, B.B.; Zillmer, R.C.
1989-01-10T23:59:59.000Z
A process is described for retarding the flow of fluid in a subterranean formation, comprising: (a) introducing an effective amount of a gel-forming composition into a subterranean formation, the gel-forming composition being operable when gelled in the formation for retarding the flow of fluid therein. The gel-forming composition consists of: i. a first substance dissolved in water to form an aqueous solution, the first substance being selected from the group consisting of polyvivyl alcohols, and mixtures thereof, wherein the gel-forming composition contains an amount of the first substance of from about 0.5 to about 5 weight percent of the gel-forming composition, and ii. an effective amount of glutaraldehyde which is operable for forming a weakly acidic condition having a pH from about 5.5 to less than 7 in the gel-forming composition and also operable for promoting crosslinking of the first substance and glutaraldehyde and for forming a gel from the gel-forming composition under the weakly acidic condition within a period of time no greater than about 5 days without adding an acidic catalyst to the gel-forming composition to lower the pH of the gel-forming composition below about 5.5.
SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW
santos
SEISMIC MONITORING OF. CARBON DIOXIDE FLUID FLOW. J. E. Santos. 1. , G. B. Savioli. 2. , J. M. Carcione. 3. , D. Gei. 3. 1. CONICET, IGPUBA, Fac.
Optimized Cross-Slot Flow Geometry for Microfluidic Extensional Rheometry
Haward, Simon J.
A precision-machined cross-slot flow geometry with a shape that has been optimized by numerical simulation of the fluid kinematics is fabricated and used to measure the extensional viscosity of a dilute polymer solution. ...
Application of Neutron Imaging and Scattering to Fluid Flow and...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS Environments Application of Neutron Imaging and Scattering to Fluid Flow and Fracture in EGS...
Fluid flow control with transformation media
Urzhumov, Yaroslav A
2011-01-01T23:59:59.000Z
We introduce a new concept for the manipulation of fluid flow around three-dimensional bodies. Inspired by transformation optics, the concept is based on a mathematical idea of coordinate transformations, and physically implemented with anisotropic porous media permeable to the flow of fluids. In two different situations - for an impermeable object situated either in a free-flowing fluid or in a fluid-filled porous medium - we show that the object can be coated with a properly chosen inhomogeneous, anisotropic permeable medium, such as to preserve the streamlines of flow and the pressure distribution that would have existed in the absence of the object. The proposed fluid flow cloak completely eliminates any disturbance of the flow by the object, including the downstream wake. Consequently, the structure helps prevent the onset of turbulence by keeping the flow laminar even above the typical critical Reynolds number for the object of the same shape and size. The cloak also cancels the viscous drag force. This...
Network Flow Optimization under Uncertainty
Tesfatsion, Leigh
Network model in words Minimize the cost of satisfying demands for electric energy By: imports, exports and electricity Subject to: conservation of energy flows (net after losses), lower and upper bounds on flows is a reactive approach: how would the optimal solution have changed if I'd only known? · Proactive approaches
Directed flow fluid rinse trough
Kempka, S.N.; Walters, R.N.
1996-07-02T23:59:59.000Z
Novel rinse troughs accomplish thorough uniform rinsing. The tanks are suitable for one or more essentially planar items having substantially the same shape. The troughs ensure that each surface is rinsed uniformly. The new troughs also require less rinse fluid to accomplish a thorough rinse than prior art troughs. 9 figs.
The stability of viscoelastic fluids in complex flows : the role of shear and extensional rheology
Rothstein, Jonathan P. (Jonathan Philip), 1974-
2001-01-01T23:59:59.000Z
Understanding the flow of polymeric fluids is important for optimizing commercial processes such as injection molding and fiber spinning. The combination of streamwise curvature and elastic normal stresses can lead to the ...
Method and apparatus for controlling fluid flow
Miller, J.R.
1980-06-27T23:59:59.000Z
A method and apparatus for precisely controlling the rate (and hence amount) of fluid flow are given. The controlled flow rate is finely adjustable, can be extremely small (on the order of microliter-atmospheres per second), can be adjusted to zero (flow stopped), and is stable to better than 1% with time. The dead volume of the valve can be made arbitrarily small, in fact essentially zero. The valve employs no wearing mechanical parts (including springs, stems, or seals). The valve is finely adjustable, has a flow rate dynamic range of many decades, can be made compatible with any fluid, and is suitable for incorporation into an open or closed loop servo-control system.
Li, Zhuoyi
2011-02-22T23:59:59.000Z
be used to obtain downhole flow conditions, which is key information to control and optimize horizontal well production. However, the fluid flow in the reservoir is often multiphase and complex, which makes temperature and pressure interpretation very...
Shear flow instabilities in viscoelastic fluids
Miller, Joel C.
2006-05-23T23:59:59.000Z
- stabilities may be desirable: for example in microfluidics it may be necessary 2to mix two fluids together. This is made difficult by the small length scales and resulting low Reynolds number. An instability which mixes the entire flow is needed. Part I...
Ultrasonic fluid flow measurement method and apparatus
Kronberg, J.W.
1993-10-12T23:59:59.000Z
An apparatus for measuring the flow of a fluid in a pipe using ultrasonic waves. The apparatus comprises an ultrasonic generator, a lens for focusing the sound energy produced by the generator, and means for directing the focused energy into the side of the pipe through an opening and in a direction close to parallel to the long axis of the pipe. A cone carries the sound energy to the lens from the generator. Depending on the choice of materials, there may be a quarter-wave, acoustic impedance matching section between the generator and the cone to reduce the reflections of energy at the cone boundary. The lens material has an acoustic impedance similar to that of the cone material but a different sonic velocity so that the lens can converge the sound waves in the fluid. A transition section between the lens and the fluid helps to couple the energy to the fluid and assures it is directed as close to parallel to the fluid flow direction as possible. 3 figures.
Ultrasonic fluid flow measurement method and apparatus
Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)
1993-01-01T23:59:59.000Z
An apparatus for measuring the flow of a fluid in a pipe using ultrasonic waves. The apparatus comprises an ultrasonic generator, a lens for focusing the sound energy produced by the generator, and means for directing the focused energy into the side of the pipe through an opening and in a direction close to parallel to the long axis of the pipe. A cone carries the sound energy to the lens from the generator. Depending on the choice of materials, there may be a quarter-wave, acoustic impedance matching section between the generator and the cone to reduce the reflections of energy at the cone boundary. The lens material has an acoustic impedance similar to that of the cone material but a different sonic velocity so that the lens can converge the sound waves in the fluid. A transition section between the lens and the fluid helps to couple the energy to the fluid and assures it is directed as close to parallel to the fluid flow direction as possible.
Optimal Power Flow Incorporating Voltage Collapse Constraints
Cañizares, Claudio A.
Optimal Power Flow Incorporating Voltage Collapse Constraints William Rosehart Claudio Ca on the current operating con- ditions is presented. Second, an Optimal Power Flow formulation that incorporates: Voltage Collapse, Optimal Power Flow, Bifur- cations. I. Introduction As open-access market principles
Numerical simulation of two-phase fluid flow
2013-01-30T23:59:59.000Z
diffusive wave (see also Carcione, 2007). Hence, fluid flow and pressure diffusion are phenomena described by the same differential equation. In hydrology and...
A Mixed Finite Element Framework for Modeling Coupled Fluid Flow ...
Birendra Jha
2005-10-03T23:59:59.000Z
and in enhanced oil recovery techniques such as steam assisted gravity ..... When fluid flows through a porous medium there are three forces acting, per unit.
Fluid flow plate for decreased density of fuel cell assembly
Vitale, Nicholas G. (Albany, NY)
1999-01-01T23:59:59.000Z
A fluid flow plate includes first and second outward faces. Each of the outward faces has a flow channel thereon for carrying respective fluid. At least one of the fluids serves as reactant fluid for a fuel cell of a fuel cell assembly. One or more pockets are formed between the first and second outward faces for decreasing density of the fluid flow plate. A given flow channel can include one or more end sections and an intermediate section. An interposed member can be positioned between the outward faces at an interface between an intermediate section, of one of the outward faces, and an end section, of that outward face. The interposed member can serve to isolate the reactant fluid from the opposing outward face. The intermediate section(s) of flow channel(s) on an outward face are preferably formed as a folded expanse.
Global Optimization of Optimal Power Flow
Grossmann, Ignacio E.
/03/2013 4 Power balance Power flows Physical limits Nonconvex constraints #12;8/26/2013 2 SDP Relaxation renewables into the grid e.g., Wind: Hard to forecast. Base load power plants cannot change their output problems. Multi-Period OPF Formulation 12/03/2013 9 Power balance Power flows Physical limits Storage
PARAMETER AND SYSTEM IDENTIFICATION FOR FLUID FLOW IN UNDERGROUND RESERVOIRS
Ewing, Richard E.
associated with two seem ingly disparate applications: production of petroleum and the remediation of water procedures associated with injection and production wells. Equations to describe the flow of fluids in porous. Such data can include pressure and flow rates of various fluid phases obtained during production, or during
Applying uncertainty quantification to multiphase flow computational fluid dynamics
Gel, A.; Garg, R.; Tong, C.; Shahnam, M.; Guenther, C.
2013-07-01T23:59:59.000Z
Multiphase computational fluid dynamics plays a major role in design and optimization of fossil fuel based reactors. There is a growing interest in accounting for the influence of uncertainties associated with physical systems to increase the reliability of computational simulation based engineering analysis. The U.S. Department of Energy's National Energy Technology Laboratory (NETL) has recently undertaken an initiative to characterize uncertainties associated with computer simulation of reacting multiphase flows encountered in energy producing systems such as a coal gasifier. The current work presents the preliminary results in applying non-intrusive parametric uncertainty quantification and propagation techniques with NETL's open-source multiphase computational fluid dynamics software MFIX. For this purpose an open-source uncertainty quantification toolkit, PSUADE developed at the Lawrence Livermore National Laboratory (LLNL) has been interfaced with MFIX software. In this study, the sources of uncertainty associated with numerical approximation and model form have been neglected, and only the model input parametric uncertainty with forward propagation has been investigated by constructing a surrogate model based on data-fitted response surface for a multiphase flow demonstration problem. Monte Carlo simulation was employed for forward propagation of the aleatory type input uncertainties. Several insights gained based on the outcome of these simulations are presented such as how inadequate characterization of uncertainties can affect the reliability of the prediction results. Also a global sensitivity study using Sobol' indices was performed to better understand the contribution of input parameters to the variability observed in response variable.
Method and apparatus for chemically altering fluids in continuous flow
Heath, W.O.; Virden, J.W. Jr.; Richardson, R.L.; Bergsman, T.M.
1993-10-19T23:59:59.000Z
The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation. 4 figures.
Method and apparatus for chemically altering fluids in continuous flow
Heath, William O. (Richland, WA); Virden, Jr., Judson W. (Richland, WA); Richardson, R. L. (West Richland, WA); Bergsman, Theresa M. (Richland, WA)
1993-01-01T23:59:59.000Z
The present invention relates to a continuous flow fluid reactor for chemically altering fluids. The reactor operates on standard frequency (50 to 60 Hz) electricity. The fluid reactor contains particles that are energized by the electricity to form a corona throughout the volume of the reactor and subsequently a non-equilibrium plasma that interacts with the fluid. Particles may form a fixed bed or a fluid bed. Electricity may be provided through electrodes or through an inductive coil. Fluids include gases containing exhaust products and organic fuels requiring oxidation.
Optimal Power Flow Based Demand Response Offer Price Optimization
Lavaei, Javad
Optimal Power Flow Based Demand Response Offer Price Optimization Zhen Qiu 1 Introduction-time energy balance. Demand response programs are offered by the utility companies to reduce the load response cost in exchange for load reduction. A considerable amount of papers have discussed the demand
Flow networks: A characterization of geophysical fluid transport
Enrico Ser-Giacomi; Vincent Rossi; Cristobal Lopez; Emilio Hernandez-Garcia
2015-03-05T23:59:59.000Z
We represent transport between different regions of a fluid domain by flow networks, constructed from the discrete representation of the Perron-Frobenius or transfer operator associated to the fluid advection dynamics. The procedure is useful to analyze fluid dynamics in geophysical contexts, as illustrated by the construction of a flow network associated to the surface circulation in the Mediterranean sea. We use network-theory tools to analyze the flow network and gain insights into transport processes. In particular we quantitatively relate dispersion and mixing characteristics, classically quantified by Lyapunov exponents, to the degree of the network nodes. A family of network entropies is defined from the network adjacency matrix, and related to the statistics of stretching in the fluid, in particular to the Lyapunov exponent field. Finally we use a network community detection algorithm, Infomap, to partition the Mediterranean network into coherent regions, i.e. areas internally well mixed, but with little fluid interchange between them.
MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN
MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN A FINITE ELEMENT for the modeling of geomechanical effects induced by reservoir production/injection and the cyclic dependence
Controls on Fault-Hosted Fluid Flow: Preliminary Results from...
Geothermal Field, CA Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Controls on Fault-Hosted Fluid Flow: Preliminary Results from the...
Can We Accurately Model Fluid Flow in Shale?
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
2013 00:00 Over 20 trillion cubic meters of natural gas are trapped in shale, but many shale oil and gas producers still use models of underground fluid flow that date back to...
On the acceleration potential in perfect fluid flow
Maestri, Raymond Rudolph
1960-01-01T23:59:59.000Z
ON THE ACCELERATION POTENTIAL IN PERFECT FLUID FLOW A Thesis By RAYMOND RUDOLPH MAESTRI Submitted. to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfrllment of the requirements for the degree of MASTER... OF SCIENCE August, 1960 Department of Aeronautical Engineering Major Subject: Aeronautical Engineering ON THE ACCELERATION POTENTIAL IN PERFECT FLUID FLOW A Thesis RAYMOND RUDOLPH MAESTRI Approved as to style and content by: Chairman of Commit e...
System and method measuring fluid flow in a conduit
Ortiz, Marcos German (Idaho Falls, ID); Kidd, Terrel G. (Blackfoot, ID)
1999-01-01T23:59:59.000Z
A system for measuring fluid mass flow in a conduit in which there exists a pressure differential in the fluid between at least two spaced-apart locations in the conduit. The system includes a first pressure transducer disposed in the side of the conduit at a first location for measuring pressure of fluid at that location, a second or more pressure transducers disposed in the side of the conduit at a second location, for making multiple measurements of pressure of fluid in the conduit at that location, and a computer for computing the average pressure of the multiple measurements at the second location and for computing flow rate of fluid in the conduit from the pressure measurement by the first pressure transducer and from the average pressure calculation of the multiple measurements.
PAPER B3: PHYSICS OF FLUID FLOWS Hilary Term 2010
Read, Peter L.
,...) · Aerodynamics important advances in fluid dynamics c. 1900 still active today · Lubrication of mechanical systems · Industry e.g. gases in pipes, polymer flows · Oil extraction liquids flowing through eff n, where `effective diameter' deff 0.3 nm, say. 2 ? 10-7 m = 200 nm. In FD, we consider scales
OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS
Jost O.L. Wendt; Gregory E. Ogden; Jennifer Sinclair; Stephanus Budilarto
2001-08-20T23:59:59.000Z
The proposed research is directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This fundamental research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners to the kinetic emissions limit (below 0.2 lb./MMBTU). Experimental studies include both cold and hot flow evaluations of the following parameters: flame holder geometry, secondary air swirl, primary and secondary inlet air velocity, coal concentration in the primary air and coal particle size distribution. Hot flow experiments will also evaluate the effect of wall temperature on burner performance. Cold flow studies will be conducted with surrogate particles as well as pulverized coal. The cold flow furnace will be similar in size and geometry to the hot-flow furnace but will be designed to use a laser Doppler velocimeter/phase Doppler particle size analyzer. The results of these studies will be used to predict particle trajectories in the hot-flow furnace as well as to estimate the effect of flame holder geometry on furnace flow field. The hot-flow experiments will be conducted in a novel near-flame down-flow pulverized coal furnace. The furnace will be equipped with externally heated walls. Both reactors will be sized to minimize wall effects on particle flow fields. The cold-flow results will be compared with Fluent computation fluid dynamics model predictions and correlated with the hot-flow results with the overall goal of providing insight for novel low NO{sub x} burner geometry's.
Notes 10. A thermohydrodynamic bulk-flow model for fluid film bearings
San Andres, Luis
2009-01-01T23:59:59.000Z
The complete set of bulk-flow equations for the analysis of turbulent flow fluid film bearings. Importance of thermal effects in process fluid applications. A CFD method for solution of the bulk-flow equations....
Method, apparatus and system for controlling fluid flow
McMurtrey, Ryan D. (Idaho Falls, ID); Ginosar, Daniel M. (Idaho Falls, ID); Burch, Joesph V. (Shelley, ID)
2007-10-30T23:59:59.000Z
A system, apparatus and method of controlling the flow of a fluid are provided. In accordance with one embodiment of the present invention, a flow control device includes a valve having a flow path defined therethrough and a valve seat in communication with the flow path with a valve stem disposed in the valve seat. The valve stem and valve seat are cooperatively configured to cause mutual relative linear displacement thereof in response to rotation of the valve stem. A gear member is coupled with the rotary stem and a linear positioning member includes a portion which complementarily engages the gear member. Upon displacement of the linear positioning member along a first axis, the gear member and rotary valve stem are rotated about a second axis and the valve stem and valve seat are mutually linearly displaced to alter the flow of fluid through the valve.
Flow of Navier-Stokes Fluids in Cylindrical Elastic Tubes
Sochi, Taha
2013-01-01T23:59:59.000Z
Analytical expressions correlating the volumetric flow rate to the inlet and outlet pressures are derived for the time-independent flow of Newtonian fluids in cylindrically-shaped elastic tubes using a one-dimensional Navier-Stokes flow model with two pressure-area constitutive relations. These expressions for elastic tubes are the equivalent of Poiseuille and Poiseuille-type expressions for rigid tubes which were previously derived for the flow of Newtonian and non-Newtonian fluids under various flow conditions. Formulae and procedures for identifying the pressure field and tube geometric profile are also presented. The results are validated by a finite element method implementation. Sensible trends in the analytical and numerical results are observed and documented.
Optimal operation of a mixed fluid cascade LNG process
Skogestad, Sigurd
Optimal operation of a mixed fluid cascade LNG process Jrgen Bauck Jensen & Sigurd Skogestad distances is to first produce liquefied natural gas (LNG) and then transport the LNG by ships. At atmospheric pressure LNG has approximately 600 times the density of gaseous NG and a temperature of ap
Flow of fractal fluid in pipes: Non-integer dimensional space Vasily E. Tarasov
Tarasov, Vasily E.
Flow of fractal fluid in pipes: Non-integer dimensional space approach Vasily E. Tarasov of an incompressible viscous fractal fluid in the pipe. Fractal fluid is described as a continuum in non solution for steady flow of fractal fluid in a pipe and corresponding fractal fluid discharge are suggested
Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation
Paris-Sud XI, Université de
Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions)" #12;Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions, cavitation, fluid flow load, CFD. Abstract: The evaluation of fluid forces on the stem is important for wear
Design considerations for inverters in fluid flow control
Guggari, Mallappa Ishwarappa
1989-01-01T23:59:59.000Z
of Electric Drives for Fluid Flow Control D. Selection of Drive for Fluid Flow Application IV POWER CIRCUIT DESIGN CONSIDERATIONS 26 29 43 47 48 A. Torque Considerations B. Overload Current C. Voltage Considerations D. Power Factor E. Harmonics F... Equivalent circuit for a separately excited dc motor 3. 2 DC Drive control system 3. 3 Equivalent circuit of an Induction Motor 3. 4 Torque-speed curve of an Induction Motor 3. 5 Torque-speed curves of an Induction Motor with variable stator voltage...
Paris-Sud XI, Universit de
SUBMITTED TO THE INTERNATIONAL JOURNAL OF FLOW CONTROL, REVISED VERSION 1 Fluid Flow Control, by visualizing a fluid flow, dense flow velocity maps can be computed via optical flow techniques by diminishing the fuel consumption of their aircrafts through drag reduction [1]. In contrast, in other
Robust processing of optical flow of fluids Ashish Doshi and Adrian G. Bors, Senior Member, IEEE
Bors, Adrian
the computational fluid dynamics (CFD). Navier-Stokes equations have been extensively studied in fluid mechanics Terms--Optical flow of fluids, computational fluid dy- namics, diffusion, vortex detection I displaying fluid movement. Velocity fields, characterizing the motion of fluids can be modelled using
FLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS
Sen, Mihir
= heat, f = LO-mode, g = LO, h = LA-mode, i = negligible, j = remote heat sink 7/ 70 #12;Heat conductionFLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS Mihir Sen Department · Shallow water analogy · Vorticity dynamics · Linear stability analysis · Numerical simulations of heat
Multiscale Modeling and Simulation of Fluid Flows in Inelastic Media
Popov, Peter
in porous media (e.g. soil), Elasticity equations in heterogeneous media (concrete, asphalt), etc porous media s The Fluid-Structure interaction (FSI) problem at the microscale and numerical methods with computational solutions s Numerical upscaling of flow in deformable porous media #12;- p. 3/42 Why homogenize
Optimizing interventions for the treatment of vascular flow disruptions
Boval, Brett Lawrence
2014-01-01T23:59:59.000Z
All tissues rely on perfusion and therefore intact blood flow. When flow is disrupted the coupled interaction between the functional and fluid domains of a tissue is impeded and viability is lost. Aortic stenosis is a ...
Resistance of louvers to fluid flow
Bevier, Charles Wayland
1954-01-01T23:59:59.000Z
as with shape and postion. This may be explained by the fact that geomet- rical similarity does not necessarily irqply mechanical similarity It has been proved that mechanical similarity with a given geometrical similarity is insured only if the ratio... arrangement. Table I gives a summary of the various louver arrangements tested. The maximum rate of air flow through the louver de- pended upon the output of the centrifugal fan used for the air source, For wide spacing of the louver boards (large free...
Device and method for measuring multi-phase fluid flow in a conduit using an elbow flow meter
Ortiz, Marcos G. (Idaho Falls, ID); Boucher, Timothy J. (Helena, MT)
1997-01-01T23:59:59.000Z
A system for measuring fluid flow in a conduit. The system utilizes pressure transducers disposed generally in line upstream and downstream of the flow of fluid in a bend in the conduit. Data from the pressure transducers is transmitted to a microprocessor or computer. The pressure differential measured by the pressure transducers is then used to calculate the fluid flow rate in the conduit. Control signals may then be generated by the microprocessor or computer to control flow, total fluid dispersed, (in, for example, an irrigation system), area of dispersal or other desired effect based on the fluid flow in the conduit.
Device and method for measuring multi-phase fluid flow in a conduit using an elbow flow meter
Ortiz, M.G.; Boucher, T.J.
1997-06-24T23:59:59.000Z
A system is described for measuring fluid flow in a conduit. The system utilizes pressure transducers disposed generally in line upstream and downstream of the flow of fluid in a bend in the conduit. Data from the pressure transducers is transmitted to a microprocessor or computer. The pressure differential measured by the pressure transducers is then used to calculate the fluid flow rate in the conduit. Control signals may then be generated by the microprocessor or computer to control flow, total fluid dispersed, (in, for example, an irrigation system), area of dispersal or other desired effect based on the fluid flow in the conduit. 2 figs.
Notes 10. A thermohydrodynamic bulk-flow model for fluid film bearings
San Andres, Luis
2009-01-01T23:59:59.000Z
Notes 10. THERMOHYDRODYNAMIC BULK-FLOW MODEL IN THIN FILM LUBRICATION ? Dr. Luis San Andr?s (2009) 1 Notes 10. Thermohydrodynamic Bulk-Flow Model in Thin Film Lubrication General flow characteristics in oil lubricated fluid film... regimes Notes 10. THERMOHYDRODYNAMIC BULK-FLOW MODEL IN THIN FILM LUBRICATION ? Dr. Luis San Andr?s (2009) 2 Bulk-Flow Equations for Thin Fluid Films The fluid flow within a thin film region, see Fig.1, is governed by the continuity...
Preserving the Volume of Fluid Using Multi-phase Flow Approach Roman Durikovic
Durikovic, Roman
complex behaviors. We often see rising bubbles or flow of muddy water, such flows involve sev- eral fluids volume when the fluid passes through a donor cell to an acceptor cell. The VOF method was improved
Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry
Sinha, Dipen N. (Los Alamos, NM)
2007-06-12T23:59:59.000Z
An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.
Noninvasive characterization of a flowing multiphase fluid using ultrasonic interferometry
Sinha, Dipen N.
2003-11-11T23:59:59.000Z
An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.
Noninvasive Characterization Of A Flowing Multiphase Fluid Using Ultrasonic Interferometry
Sinha, Dipen N. (Los Alamos, NM)
2005-05-10T23:59:59.000Z
An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.
FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES
FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties
Stirling engine performance optimization with different working fluids
Daley, J.G.; Marr, W.W.; Heames, T.J.
1986-01-01T23:59:59.000Z
The design flexibility of Stirling cycle devices is evident from the wide variety of mechanical configurations that have been developed as well as the many differing applications that have been shown to be technically feasible. The choice of working fluid is one option that strongly influences engine design. Hydrogen permits the most compact engine (for a given power output and efficiency) of any gaseous working fluid investigated and has therefore been the choice in Stirling development programs directed at the automotive application where engine size is a major concern. Systems using helium or air are presently under development for applications where size is not as important a consideration. This paper describes calculated characteristics of engines optimized for four working fluids (hydrogen, helium, air and methane). A comparison is given between engines whose exterior dimensions are minimized and with lower rpm, lower pressure engine designs calculated by maximizing the dimensionless parameter known as the Beale number. Design point power and efficiency are the same in the resulting eight conceptual designs but great variation is shown in engine characteristics due both to working fluid differences and to the two different design objectives. 5 refs., 7 figs., 5 tabs.
Reducing or stopping the uncontrolled flow of fluid such as oil from a well
Hermes, Robert E
2014-02-18T23:59:59.000Z
The uncontrolled flow of fluid from an oil or gas well may be reduced or stopped by injecting a composition including 2-cyanoacrylate ester monomer into the fluid stream. Injection of the monomer results in a rapid, perhaps instantaneous, polymerization of the monomer within the flow stream of the fluid. This polymerization results in formation of a solid plug that reduces or stops the flow of additional fluid from the well.
Inexactness of SDP Relaxation for Optimal Power Flow over Radial ...
Burak Kocuk
2014-10-03T23:59:59.000Z
Oct 3, 2014 ... Abstract: It has been recently proven that the semidefinite programming (SDP) relaxation of the optimal power flow problem over radial...
The flow and heat transfer in a viscous fluid over an unsteady stretching surface
Ene, Remus-Daniel; Marinca, Bogdan
2015-01-01T23:59:59.000Z
In this paper we have studied the flow and heat transfer in a viscous fluid by a horizontal sheet. The stretching rate and temperature of the sheet vary with time. The governing equations for momentum and thermal energy are reduced to ordinary differential equations by means of similarity transformation. These equations are solved approximately by means of the Optimal Homotopy Asymptotic Method (OHAM) which provides us with a convenient way to control the convergence of approximation solutions and adjust convergence rigorous when necessary. Some examples are given and the results obtained reveal that the proposed method is effective and easy to use.
Stable loosely-coupled-type algorithm for fluid-structure interaction in blood flow
Guidoboni, Giovanna
Stable loosely-coupled-type algorithm for fluid-structure interaction in blood flow Giovanna Abstract We introduce a novel loosely coupled-type algorithm for fluid-structure interaction between blood. A major application is blood flow in human arteries. Understanding fluid- structure interaction between
Influence of formation clays on the flow of aqueous fluids
Hower, W.F.
1981-01-01T23:59:59.000Z
Most sandstone formations contain clays that can have a significant effect on the flow of aqueous fluids. The clays most frequently detected are smectite, mixed layer, illite, kaolinite, and chlorite. All of these clays are capable of migrating and causing permeability damage when they are contacted by waters foreign to the formation. Normally, these waters alter ionic environments around the clays, which causes the clays to be dislodged from their original positions. Thus, any time clay is present in the rock, it can be assumed that permeability damage can occur. The degree of damage depends upon the concentration and types of clays present, their relative position in the rock, the severity of the ionic environmental change; and fluid velocity. Permeability damage has been minimized in oil and gas wells through the use of potassium and ammonium ions. 15 references.
Fluid flow and heat transfer modeling for castings
Domanus, H.M.; Liu, Y.Y.; Sha, W.T.
1986-01-01T23:59:59.000Z
Casting is fundamental to manufacturing of many types of equipment and products. Although casting is a very old technology that has been in existence for hundreds of years, it remains a highly empirical technology, and production of new castings requires an expensive and time-consuming trial-and-error approach. In recent years, mathematical modeling of casting has received increasing attention; however, a majority of the modeling work has been in the area of heat transfer and solidification. Very little work has been done in modeling fluid flow of the liquid melt. This paper presents a model of fluid flow coupled with heat transfer of a liquid melt for casting processes. The model to be described in this paper is an extension of the COMMIX code and is capable of handling castings with any shape, size, and material. A feature of this model is the ability to track the liquid/gas interface and liquid/solid interface. The flow of liquid melt through the sprue and runners and into the mold cavity is calculated as well as three-dimensional temperature and velocity distributions of the liquid melt throughout the casting process. 14 refs., 13 figs.
A COMPUTATIONAL ANALYSIS OF THE OPTIMAL POWER FLOW PROBLEM
algorithms to handle this problem for the e - 1 security constrained optimal power flow problem. We also.3. The MATPOWER package 4 2.4. Graph theoretic notions 4 3. Security constrained optimal power flow 5 3, such as the breakdown of a generator or a fault in some transmission line. The importance of being able to supply power
Microscale Fluid Flow Induced by Thermoviscous Expansion Along a Traveling Wave Franz M. Weinert,1
Kersting, Roland
are negli- gible if the velocities are small with respect to the speed of sound, fluid flow is essentially confinement of a liquid changes its flow behavior markedly since the importance of surface forces relative a novel mechanism to generate net flow in a thin fluid chamber, i.e., a viscous liquid confined between
Computational Fluids Dynamics and its Application to Multiphase Flows (3 credits)
Chen, Zheng
Computational Fluids Dynamics and its Application to Multiphase Flows (3 credits) Instructor Eric CLIMENT, Dept. of Fluids Mechanics, INP-ENSEEIHT / IMFT (eric.climent@imft.fr) Synopsis Multiphase flows will be introduced, together with their applications to multiphase flows (dispersion, two-way coupling, modelling
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Boyer, Edmond
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S modeling of the turbulent flow in a rotor-stator cavity subjected to a superimposed throughflow with heat the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial
Hydrostatic bearings for a turbine fluid flow metering device
Fincke, James R. (Rigby, ID)
1982-01-01T23:59:59.000Z
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.
Hydrostatic bearings for a turbine fluid flow metering device
Fincke, J.R.
1982-05-04T23:59:59.000Z
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion. 3 figs.
Multiphase fluid flow and time lapse seismics UNLP, 11 Octubre de ...
santos
Time-lapse seismic surveys aim to monitor the migration and dispersal of the CO2 plume after injection. Multiphase fluid flow and time lapse seismics p. 3...
Wave-induced fluid flow in random porous media: Attenuation and ...
2005-04-20T23:59:59.000Z
wave attenuation and dispersion due to wave-induced fluid flow in 3-D randomly inhomogeneous .... tenuation is controlled by the integrand, that is, by the prod-.
Hydrostatic bearings for a turbine fluid flow metering device
Fincke, J.R.
1980-05-02T23:59:59.000Z
A rotor assembly fluid metering device has been improved by development of a hydrostatic bearing fluid system which provides bearing fluid at a common pressure to rotor assembly bearing surfaces. The bearing fluid distribution system produces a uniform film of fluid distribution system produces a uniform film of fluid between bearing surfaces and allows rapid replacement of bearing fluid between bearing surfaces, thereby minimizing bearing wear and corrosion.
Winters, W.S.
1984-01-01T23:59:59.000Z
An overview of the computer code TOPAZ (Transient-One-Dimensional Pipe Flow Analyzer) is presented. TOPAZ models the flow of compressible and incompressible fluids through complex and arbitrary arrangements of pipes, valves, flow branches and vessels. Heat transfer to and from the fluid containment structures (i.e. vessel and pipe walls) can also be modeled. This document includes discussions of the fluid flow equations and containment heat conduction equations. The modeling philosophy, numerical integration technique, code architecture, and methods for generating the computational mesh are also discussed.
Advanced tomographic flow diagnostics for opaque multiphase fluids
Torczynski, J.R.; O`Hern, T.J.; Adkins, D.R.; Jackson, N.B.; Shollenberger, K.A.
1997-05-01T23:59:59.000Z
This report documents the work performed for the ``Advanced Tomographic Flow Diagnostics for Opaque Multiphase Fluids`` LDRD (Laboratory-Directed Research and Development) project and is presented as the fulfillment of the LDRD reporting requirement. Dispersed multiphase flows, particularly gas-liquid flows, are industrially important to the chemical and applied-energy industries, where bubble-column reactors are employed for chemical synthesis and waste treatment. Due to the large range of length scales (10{sup {minus}6}-10{sup 1}m) inherent in real systems, direct numerical simulation is not possible at present, so computational simulations are forced to use models of subgrid-scale processes, the accuracy of which strongly impacts simulation fidelity. The development and validation of such subgrid-scale models requires data sets at representative conditions. The ideal measurement techniques would provide spatially and temporally resolved full-field measurements of the distributions of all phases, their velocity fields, and additional associated quantities such as pressure and temperature. No technique or set of techniques is known that satisfies this requirement. In this study, efforts are focused on characterizing the spatial distribution of the phases in two-phase gas-liquid flow and in three-phase gas-liquid-solid flow. Due to its industrial importance, the bubble-column geometry is selected for diagnostics development and assessment. Two bubble-column testbeds are utilized: one at laboratory scale and one close to industrial scale. Several techniques for measuring the phase distributions at conditions of industrial interest are examined: level-rise measurements, differential-pressure measurements, bulk electrical impedance measurements, electrical bubble probes, x-ray tomography, gamma-densitometry tomography, and electrical impedance tomography.
System and method for bidirectional flow and controlling fluid flow in a conduit
Ortiz, M.G.
1999-03-23T23:59:59.000Z
A system for measuring bidirectional flow, including backflow, of fluid in a conduit is disclosed. The system utilizes a structural mechanism to create a pressure differential in the conduit. Pressure sensors are positioned upstream from the mechanism, at the mechanism, and downstream from the mechanism. Data from the pressure sensors are transmitted to a microprocessor or computer, and pressure differential detected between the pressure sensors is then used to calculate the backflow. Control signals may then be generated by the microprocessor or computer to shut off valves located in the conduit, upon the occurrence of backflow, or to control flow, total material dispersed, etc. in the conduit. 3 figs.
System and method for bidirectional flow and controlling fluid flow in a conduit
Ortiz, Marcos German (Idaho Falls, ID)
1999-01-01T23:59:59.000Z
A system for measuring bidirectional flow, including backflow, of fluid in a conduit. The system utilizes a structural mechanism to create a pressure differential in the conduit. Pressure sensors are positioned upstream from the mechanism, at the mechanism, and downstream from the mechanism. Data from the pressure sensors are transmitted to a microprocessor or computer, and pressure differential detected between the pressure sensors is then used to calculate the backflow. Control signals may then be generated by the microprocessor or computer to shut off valves located in the conduit, upon the occurrence of backflow, or to control flow, total material dispersed, etc. in the conduit.
Coupled fluid flow and geomechanical deformation modeling Susan E. Minkoff a,*, C. Mike Stoneb,1
Minkoff, Susan E.
Coupled fluid flow and geomechanical deformation modeling Susan E. Minkoff a,*, C. Mike Stoneb,1 reservoir properties. Pore pressures from flow are used as loads for the geomechanics code
Optimal mixing and optimal stirring for fixed energy, fixed power or fixed palenstrophy flows
Novikov, Alexei
Optimal mixing and optimal stirring for fixed energy, fixed power or fixed palenstrophy flows-time perfect mixing with a finite energy constraint on the stirring flow. On the other hand, using techniques, University of Michigan, Ann Arbor, MI 48109 (Dated: 31 March 2012) We consider passive scalar mixing
A NOVEL FLUID FLOW MODEL WITH MEMORY FOR POROUS MEDIA APPLICATIONS
Hossain, M. Enamul
thickness, rock and fluid properties independent of pressure and laminar flow are reported in many the rock and fluid properties to be constant in time. It is very important to consider the variation to consider the time variation of fluid and rock properties in a proper way. Therefore, Darcys law should
Variational principle for optimal accelerated neutralized flow A. Fruchtman
Variational principle for optimal accelerated neutralized flow A. Fruchtman Holon Academic Institute of Technology, 52 Golomb Street, P.O. Box 305, Holon 58102, Israel N. J. Fisch Princeton Plasma
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 2
Not Available
1992-06-01T23:59:59.000Z
The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the thermal sciences. The handbook includes information on thermodynamics and the properties of fluids; the three modes of heat transfer -- conduction, convection, and radiation; and fluid flow, and the energy relationships in fluid systems. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility fluid systems.
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 1
Not Available
1992-06-01T23:59:59.000Z
The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the thermal sciences. The handbook includes information on thermodynamics and the properties of fluids; the three modes of heat transfer -- conduction, convection, and radiation; and fluid flow, and the energy relationships in fluid systems. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility fluid systems.
DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 3
Not Available
1992-06-01T23:59:59.000Z
The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the thermal sciences. The handbook includes information on thermodynamics and the properties of fluids; the three modes of heat transfer -- conduction, convection, and radiation; and fluid flow, and the energy relationships in fluid systems. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility fluid systems.
Device and method for measuring fluid flow in a conduit having a gradual bend
Ortiz, M.G.; Boucher, T.J.
1998-11-10T23:59:59.000Z
A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.
Numerical Simulation of the Flow of a Power Law Fluid in an Elbow Bend
Kanakamedala, Karthik
2010-07-14T23:59:59.000Z
A numerical study of flow of power law fluid in an elbow bend has been carried out. The motivation behind this study is to analyze the velocity profiles, especially the pattern of the secondary flow of power law fluid in a bend as there are several...
Valle, Martin
coupled fluid flow and geomechanical fault-slip analysis J. Rutqvist *, J. Birkholzer, F. Cappa, C demonstrates the use of coupled fluid flow and geomechanical fault slip (fault reactivation) analysis: Geological CO2 sequestration; geomechanics; Fault slip; Stress; Caprock integrity; CO2 injection 1
Network model of fluid flow in semi-solid aluminum alloys W.O. Dijkstra a
Vuik, Kees
Network model of fluid flow in semi-solid aluminum alloys W.O. Dijkstra a , C. Vuik b , L within a semi-solid aluminum alloy. The model consists of a set of connected channels representing; Fluid flow; Aluminum alloys; Permeability; Macrosegregation 1. Introduction Early simulations
An Analysis of Heat and Fluid Flow Phenomena 1n Electroslag Welding
Eagar, Thomas W.
and temperature distri- bution~ are given for several idealized models of the electroslag welding process) ) An Analysis of Heat and Fluid Flow Phenomena 1n Electroslag Welding Two physical models created and fluid flow phenom- ena in metals processing operations have been applied to electroslag weld- ing
Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law
Boyer, Edmond
Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law F transfer in a magnetic fluid flow under the action of an applied magnetic field. Instead of the usual heat-Cattaneo law, heat transfer, magnetic field, magnetization AMS subject classifications: 76N10, 35Q35. 1
Characterization of fracture networks for fluid flow analysis
Long, J.C.S.; Billaux, D.; Hestir, K.; Majer, E.L.; Peterson, J.; Karasaki, K.; Nihei, K.; Gentier, S.; Cox, L.
1989-06-01T23:59:59.000Z
The analysis of fluid flow through fractured rocks is difficult because the only way to assign hydraulic parameters to fractures is to perform hydraulic tests. However, the interpretation of such tests, or ''inversion'' of the data, requires at least that we know the geometric pattern formed by the fractures. Combining a statistical approach with geophysical data may be extremely helpful in defining the fracture geometry. Cross-hole geophysics, either seismic or radar, can provide tomograms which are pixel maps of the velocity or attenuation anomalies in the rock. These anomalies are often due to fracture zones. Therefore, tomograms can be used to identify fracture zones and provide information about the structure within the fracture zones. This structural information can be used as the basis for simulating the degree of fracturing within the zones. Well tests can then be used to further refine the model. Because the fracture network is only partially connected, the resulting geometry of the flow paths may have fractal properties. We are studying the behavior of well tests under such geometry. Through understanding of this behavior, it may be possible to use inverse techniques to refine the a priori assignment of fractures and their conductances such that we obtain the best fit to a series of well test results simultaneously. The methodology described here is under development and currently being applied to several field sites. 4 refs., 14 figs.
Optimizing drilling performance using a selected drilling fluid
Judzis, Arnis (Salt Lake City, UT); Black, Alan D. (Coral Springs, FL); Green, Sidney J. (Salt Lake City, UT); Robertson, Homer A. (West Jordan, UT); Bland, Ronald G. (Houston, TX); Curry, David Alexander (The Woodlands, TX); Ledgerwood, III, Leroy W. (Cypress, TX)
2011-04-19T23:59:59.000Z
To improve drilling performance, a drilling fluid is selected based on one or more criteria and to have at least one target characteristic. Drilling equipment is used to drill a wellbore, and the selected drilling fluid is provided into the wellbore during drilling with the drilling equipment. The at least one target characteristic of the drilling fluid includes an ability of the drilling fluid to penetrate into formation cuttings during drilling to weaken the formation cuttings.
Kim, J.
2014-01-01T23:59:59.000Z
Settari A. Modeling of geomechanics in naturally fracturedway coupled fluid flow and geomechanics in hydrate deposits.for coupled flow and geomechanics: Drained and undrained
Numerical schemes for dynamically orthogonal equations of stochastic fluid and ocean flows
Ueckermann, M.P., E-mail: mpuecker@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States); Lermusiaux, P.F.J., E-mail: pierrel@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States)] [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States); Sapsis, T.P., E-mail: sapsis@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Mass. Avenue, Cambridge, MA 02139 (United States)
2013-01-15T23:59:59.000Z
The quantification of uncertainties is critical when systems are nonlinear and have uncertain terms in their governing equations or are constrained by limited knowledge of initial and boundary conditions. Such situations are common in multiscale, intermittent and non-homogeneous fluid and ocean flows. The dynamically orthogonal (DO) field equations provide an adaptive methodology to predict the probability density functions of such flows. The present work derives efficient computational schemes for the DO methodology applied to unsteady stochastic Navier-Stokes and Boussinesq equations, and illustrates and studies the numerical aspects of these schemes. Semi-implicit projection methods are developed for the mean and for the DO modes, and time-marching schemes of first to fourth order are used for the stochastic coefficients. Conservative second-order finite-volumes are employed in physical space with new advection schemes based on total variation diminishing methods. Other results include: (i) the definition of pseudo-stochastic pressures to obtain a number of pressure equations that is linear in the subspace size instead of quadratic; (ii) symmetric advection schemes for the stochastic velocities; (iii) the use of generalized inversion to deal with singular subspace covariances or deterministic modes; and (iv) schemes to maintain orthonormal modes at the numerical level. To verify our implementation and study the properties of our schemes and their variations, a set of stochastic flow benchmarks are defined including asymmetric Dirac and symmetric lock-exchange flows, lid-driven cavity flows, and flows past objects in a confined channel. Different Reynolds number and Grashof number regimes are employed to illustrate robustness. Optimal convergence under both time and space refinements is shown as well as the convergence of the probability density functions with the number of stochastic realizations.
Magnetic fluid flow phenomena in DC and rotating magnetic fields
Rhodes, Scott E. (Scott Edward), 1981-
2004-01-01T23:59:59.000Z
An investigation of magnetic fluid experiments and analysis is presented in three parts: a study of magnetic field induced torques in magnetorheological fluids, a characterization and quantitative measurement of properties ...
Time-lapse seismic monitoring of subsurface fluid flow
Yuh, Sung H.
2004-09-30T23:59:59.000Z
Time-lapse seismic monitoring repeats 3D seismic imaging over a reservoir to map fluid movements in a reservoir. During hydrocarbon production, the fluid saturation, pressure, and temperature of a reservoir change, thereby altering the acoustic...
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 Molecular dynamics methods in
Maruyama, Shigeo
2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 2.13.7 Molecular dynamics methods in microscale heat transfer Shigeo Maruyama A. Introduction In normal heat transfer and fluid flow calculations of molecules. This situation is approached in microscale heat transfer and fluid flow. Molecular level
FORTRAN SUBROUTINES FOR NETWORK FLOW OPTIMIZATION ...
2004-03-13T23:59:59.000Z
Mar 13, 2004 ... cost network flow problem can be formulated as min. ?. (i,j)?E cijxij ...... The control parameters are then read from the vector info, with pdginf()...
Method and apparatus for measuring the mass flow rate of a fluid
Evans, Robert P. (Idaho Falls, ID); Wilkins, S. Curtis (Idaho Falls, ID); Goodrich, Lorenzo D. (Shelley, ID); Blotter, Jonathan D. (Pocatello, ID)
2002-01-01T23:59:59.000Z
A non invasive method and apparatus is provided to measure the mass flow rate of a multi-phase fluid. An accelerometer is attached to a pipe carrying a multi-phase fluid. Flow related measurements in pipes are sensitive to random velocity fluctuations whose magnitude is proportional to the mean mass flow rate. An analysis of the signal produced by the accelerometer shows a relationship between the mass flow of a fluid and the noise component of the signal of an accelerometer. The noise signal, as defined by the standard deviation of the accelerometer signal allows the method and apparatus of the present invention to non-intrusively measure the mass flow rate of a multi-phase fluid.
Single-cycle mixed-fluid LNG process Part I: Optimal design
Skogestad, Sigurd
Single-cycle mixed-fluid LNG process Part I: Optimal design Jrgen Bauck Jensen and Sigurd the design optimization of a relatively simple LNG pro- cess; the PRICO process. A simple economic objective. Keywords: PRICO, LNG, design 1 Introduction Stebbing and O'Brien (1975) reported on the performance
Efficient Production Optimization Using Flow Network Models
Lerlertpakdee, Pongsathorn
2012-10-19T23:59:59.000Z
of the physical processes that govern the long-term behavior of the reservoir. We present an alternative solution that combines the advantages of both statistics-based and physics-based methods by deriving the flow predictions in complex two-dimensional models...
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir...
Broader source: Energy.gov (indexed) [DOE]
model fluid injection into a tight reservoir on the edges of a hydrothermal field. Use seismic data to constrain geomechanicalhydrologicthermal model of reservoir....
Monitoring and Modeling Fluid Flow in a Developing Enhanced Geothermal...
Broader source: Energy.gov (indexed) [DOE]
fluid injection into a tight reservoir on the edges of a hydrothermal field; to use seismic data to constrain geomechanicalhydrologicthermal model of reservoir; to model for...
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir
Broader source: Energy.gov (indexed) [DOE]
fluid injection into a tight reservoir on the edges of a hydrothermal field * Use seismic data to constrain geomechanicalhydrologicthermal model of reservoir * Model for...
Analysis of multiphase fluid flows via high speed and synthetic aperture three dimensional imaging
Scharfman, Barry Ethan
2012-01-01T23:59:59.000Z
Spray flows are a difficult problem within the realm of fluid mechanics because of the complicated interfacial physics involved. Complete models of sprays having even the simplest geometries continue to elude researchers ...
IN SITU STRESS, FRACTURE, AND FLUID FLOW ANALYSIS IN WELL 38C...
IN THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: IN SITU STRESS, FRACTURE, AND FLUID FLOW ANALYSIS IN WELL...
IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST FLANK OF...
OF THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST...
Permeability of illite-bearing shale: 2. Influence of fluid chemistry on flow and functionally
Herbert, Bruce
Permeability of illite-bearing shale: 2. Influence of fluid chemistry on flow and functionally; accepted 14 July 2004; published 14 October 2004. [1] Bedding-parallel permeability of illite-rich shale Geochemistry: Low-temperature geochemistry; KEYWORDS: permeability, shale, fluid chemistry Citation: Kwon, O
Cartesian Cut Cell Two-Fluid Solver for Hydraulic Flow Problems
Ingram, David
Cartesian Cut Cell Two-Fluid Solver for Hydraulic Flow Problems L. Qian1 ; D. M. Causon2 ; D. M. Ingram3 ; and C. G. Mingham4 Abstract: A two-fluid solver which can be applied to a variety of hydraulic with a sloping beach is also calculated to demonstrate the applicability of the method to real hydraulic problems
Fluid Flow and Infiltration in Structured Fibrous Porous Media
Papathanasiou, Thanasis D.
2006-08-09T23:59:59.000Z
Present the results of an extensive computational investigation of flow through structured fibrous media.
Security Constrained Optimal Power Flow 1.0 Introduction and notation
McCalley, James D.
1 Security Constrained Optimal Power Flow 1.0 Introduction and notation Figure 1 below compares the optimal power flow (OPF) with the security-constrained optimal power flow (SCOPF). Fig. 1 Some comments normal flow moves from just 100% of continuous rating. SCOPF differs from an OPF solution
Spatiotemporal and geometric optimization of sensor arrays for detecting analytes fluids
Lewis, Nathan S.; Freund, Michael S.; Briglin, Shawn M.; Tokumaru, Phil; Martin, Charles R.; Mitchell, David T.
2006-10-17T23:59:59.000Z
Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.
Spatiotemporal and geometric optimization of sensor arrays for detecting analytes in fluids
Lewis, Nathan S. (La Canada, CA); Freund, Michael S. (Winnipeg, CA); Briglin, Shawn S. (Chittenango, NY); Tokumaru, Phillip (Moorpark, CA); Martin, Charles R. (Gainesville, FL); Mitchell, David (Newtown, PA)
2009-09-29T23:59:59.000Z
Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.
Mukhopadhyay, S.; Tsang, Y.; Finsterle, S.
2009-01-15T23:59:59.000Z
A simple conceptual model has been recently developed for analyzing pressure and temperature data from flowing fluid temperature logging (FFTL) in unsaturated fractured rock. Using this conceptual model, we developed an analytical solution for FFTL pressure response, and a semianalytical solution for FFTL temperature response. We also proposed a method for estimating fracture permeability from FFTL temperature data. The conceptual model was based on some simplifying assumptions, particularly that a single-phase airflow model was used. In this paper, we develop a more comprehensive numerical model of multiphase flow and heat transfer associated with FFTL. Using this numerical model, we perform a number of forward simulations to determine the parameters that have the strongest influence on the pressure and temperature response from FFTL. We then use the iTOUGH2 optimization code to estimate these most sensitive parameters through inverse modeling and to quantify the uncertainties associated with these estimated parameters. We conclude that FFTL can be utilized to determine permeability, porosity, and thermal conductivity of the fracture rock. Two other parameters, which are not properties of the fractured rock, have strong influence on FFTL response. These are pressure and temperature in the borehole that were at equilibrium with the fractured rock formation at the beginning of FFTL. We illustrate how these parameters can also be estimated from FFTL data.
Thomas, Brian G.
that is neither too cold nor too turbulent. In addition, the flow conditions should minimize exposure to air optimization. Fluid flow in the mold is controlled by many design parameters and operating conditions. Nozzle geometry is the most important, and includes the bore size, port angle, port opening size, nozzle wall
Probabilistic Optimal Power Flow Applications to Electricity Markets
Cañizares, Claudio A.
of electricity markets, special attention is paid to the uncertainty in Locational Marginal Prices (LMPs], [2]. In markets based on optimal power flows (OPF) to calculate electricity prices, one may use prices. Since OPF is a deterministic tool, it is necessary to complete many simulations to en- compass
Nonlinear optimal power flow 1.0 Some introductory comments
McCalley, James D.
1 Nonlinear optimal power flow 1.0 Some introductory comments Although the LPOPF does bring computation. We will also see that the NLOPF admits additional control capabilities that can be very useful Define: ng: number of generators N: number of buses x: state vector u: control vector Ei
DC Optimal Power Flow: Uniqueness and Chee Wei Tan
Tan, Chee Wei
and are computationally fast for practical smart power grids. I. BACKGROUND The Optimal Power Flow (OPF) problem network. The DC-OPF can be practically important in a smart grid, where there are renewables, e.g., solar implications on how algorithms can be designed to solve the OPF in a smart grid. Different from prior work
Multiphase flow and control of fluid path in microsystems
Jhunjhunwala, Manish
2005-01-01T23:59:59.000Z
Miniaturized chemical-systems are expected to have advantages of handling, portability, cost, speed, reproducibility and safety. Control of fluid path in small channels between processes in a chemical/biological network ...
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir
Broader source: Energy.gov [DOE]
Project objectives: Better understand and model fluid injection into a tight reservoir on the edges of a hydrothermal field. Use seismic data to constrain geomechanical/hydrologic/thermal model of reservoir.
Ortiz, M.G.; Boucher, T.J.
1998-10-27T23:59:59.000Z
A system is described for measuring fluid flow in a conduit having a gradual bend or arc, and a straight section. The system includes pressure transducers, one or more disposed in the conduit on the outside of the arc, and one disposed in the conduit in a straight section thereof. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.
Van Hirtum, Annemie
2008-01-01T23:59:59.000Z
, the pharynx, the mouth and the larynx (Fig. 1), is the most external part of the respiratory system. Modelling deformations has been chosen to compute the mechanical behaviour of the tongue. The main features of the flow and Depollier, 1995; Huang, 1995; Balint and Lucey, 2005), numerical simulations of the respiratory fluid flow
Numerical models of caldera deformation: Effects of multiphase and multicomponent hydrothermal studies addressing the effects of multiphase flow on crustal mechanics have been attempted. Recent numerical simulations of multiphase (liquid-gas), multicomponent (H2OCO2) hydrothermal fluid flow
1. Introduction Fluid flow in continuous casting of steel is of great inter-
Thomas, Brian G.
-phase fluid flow owing to the simulation kinematic viscosity of steel and water, the flow pattern itself and entrainment of the mold slag, · transient fluctuations and waves in the top surface level, and their effect, such as intermixing during a grade change and segregation. Extensive past work has employed physical water models
Cai, Xiao-Chuan
to blood flow modeling 6 Andrew T. Barker,a , Xiao-Chuan Caib a Department of Applied Mathematics finite element solver for the simulation of blood flow in compliant arteries. The incompressible Navier-Stokes equations are used to model the fluid and coupled to an incom- pressible linear elastic model for the blood
Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with
Paris-Sud XI, Universit de
Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with partial-Newtonian boundary layer flow and heat transfer over an exponentially stretch- ing sheet with partial slip boundary. The heat transfer analysis has been carried out for two heating processes, namely (i) with prescribed sur
Role of viscoelasticity and non-linear rheology in flows of complex fluids at high deformation rates
Ober, Thomas J. (Thomas Joseph)
2013-01-01T23:59:59.000Z
We combine pressure, velocimetry and birefringence measurements to study three phenomena for which the fluid rheology plays a dominant role: 1) shear banding in micellar fluids, 2) extension-dominated flows in microfluidic ...
Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of...
Distributions Abstract A methodology for analyzing the internal flow characteristics of a fractured geothermal reservoir using tracer-determined residence time distribution curves...
Zero Duality Gap in Optimal Power Flow Problem Javad Lavaei and Steven H. Low
Low, Steven H.
power flow (OPF) problem deals with finding an optimal operating point of a power system that mini1 Zero Duality Gap in Optimal Power Flow Problem Javad Lavaei and Steven H. Low Abstract--The optimal power flow (OPF) problem is nonconvex and generally hard to solve. In this paper, we propose
Finite volume methods for fluid flow in porous media
Hiptmair, Ralf
. . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.5 Multiphase and multicomponent flows . . . . . . . . . . . . . . . 13 2.5.1 Black-oil model . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.3.1 General solution . . . . . . . . . . . . . . . . . . . . . . . 9 2.3.2 Pressure equation . . . . . . . . . . . . . . . . . . . . . . 10 2.3.3 Pressure equation for incompressible immiscible flow . . . 11 2.3.4 Saturation equation
Parcel EulerianLagrangian fluid dynamics of rotating geophysical flows
Oliver, Marcel
, Gottwald, and Reich (2002) and Frank and Reich (2003, 2004) introduced a Hamiltonian Particle Mesh (HPM integra- tion scheme is used. The HPM method is a parcel EulerianLagrangian method: the fluid particles on the advection time scale. The conservation of mass and circulation in the HPM numerical model is shown
Jong Chull Jo; Myung Jo Jhung; Woong Sik Kim; Hho Jung Kim [Korea Institute of Nuclear Safety, 19 Kusung-dong, Yusung-gu, Taejon 305-338 (Korea, Republic of)
2004-07-01T23:59:59.000Z
This study investigates the fluid-elastic instability characteristics of steam generator helical type tubes in operating nuclear power plants. The thermal-hydraulic conditions of both tube side and shell side flow fields are predicted by a general purpose computational fluid dynamics code employing the finite volume element modeling. To get the natural frequency, corresponding mode shape and participation factor, modal analyses are performed for helical type tubes with various conditions. Investigated are the effects of the helix angle, the number of supports and the status of the inner fluid on the modal, and fluid-elastic instability characteristics of the tubes, which are expressed in terms of the natural frequency, corresponding mode shape, and stability ratio. (authors)
Rutqvist, J.
2014-01-01T23:59:59.000Z
and Mining Sciences & Geomechanics Abstracts, 1983, 20:and Mining Sciences & Geomechanics Abstracts, 1985, BerrymanL W. Coupling fluid flow and geomechanics in dual-porosity
Selecting fines recycle methods to optimize fluid bed combustor performance
Rickman, W.S.; Fields, D.E.; Brimhall, W.L.; Callahan, S.F.
1980-05-01T23:59:59.000Z
Testing and analysis of a number of different fines recycle methods for fluid bed combustors has led to a generalized modeling technique. This model accounts for the effect of pertinent variables in determining overall combustion efficiencies. Computer application of this model has allowed trade-off studies to be performed that show the overall process effects of changes in individual operating parameters. Verification of the model has been accomplished in processing campaigns while combusting fuels such as graphite and bituminous coal. A 0.4 MW test unit was used for the graphite experimental work. Solid fuel was typically crushed to 5 mm maximum screen size. Bed temperatures were normally controlled at 900/sup 0/C; the combustor was an atmospheric unit with maximum in-bed pressures of 0.2 atm. Expanded bed depths ranged from 1.5 to 3 meters. Additional data was taken from recycle tests sponsored by EPRI on the B and W 6 ft x 6 ft fluid bed combustor. These tests used high sulfur coal in a 1.2 meter deep, 850/sup 0/C atmospheric fluidized bed of limestone, with low recycle rates and temperatures. Close agreement between the model and test data has been noted, with combustion efficiency predictions matching experimental results within 1%.
Single-cycle mixed-fluid LNG process Part II: Optimal operation
Skogestad, Sigurd
Single-cycle mixed-fluid LNG process Part II: Optimal operation Jrgen Bauck Jensen and Sigurd of work that goes into the design of LNG processes, there is surprisingly little attention simple LNG process, namely the PRICO process. Keywords: PRICO, LNG, operation 1 Introduction The process
Non-Steady wall-bounded flows of viscoelastic fluids under periodic forcing
Anier Hernndez-Garca; Antonio Fernndez-Barbero; Oscar Sotolongo-Costa
2013-01-18T23:59:59.000Z
The problem of oscillating flows inside pipes under periodic forcing of viscoelastic fluids is addressed here. Starting from the linear Oldroyd-B model, a generalized Darcy's law is obtained in frequency domain and an explicit expression for the dependence of the dynamic permeability on fluid parameters and forcing frequency is derived. Previous results in both viscoelastic and Newtonian fluids are here shown to be particular cases of our results. On the basis of our calculations, a possible explanation for the observed damping of local dynamic response as the forcing frequency increases is given. Good fitting with recent experimental studies of wave propagation in viscoelastic media is here exhibited. Sound wave propagation in viscoelastic media flowing inside straight pipes is investigated. In particular, we obtain the local dynamic response for weakly compressible flows.
Effect of Fluid Flow on Inclusion Coarsening in Low-Alloy Steel Welds
Babu, S.S.; David, S.A.; DebRoy, T.; Hong, T.
1998-02-28T23:59:59.000Z
Oxide inclusions form in welds because of deoxidation reactions in the weld pool. These inclusions control the weld microstructure development. Thermodynamic and kinetic calculation of oxidation reaction can describe inclusion characteristics such as number density, size, and composition. Experimental work has shown that fluid-flow velocity gradients in the weld pool can accelerate inclusion growth by collision and coalescence. Moreover, fluid flow in welds can transport inclusions to different temperature regions that may lead to repeated dissolution and growth of inclusions. These phenomena are being studied with the help of computational coupled heat transfer, fluid-flow, thermodynamic, and kinetic models. The results show that the inclusion formation in steel welds can be described as a function of the welding processes, process parameters, and steel composition.
Porosity, Permeability, And Fluid Flow In The Yellowstone Geothermal...
section of the 0.6-Ma Lava Creek ash-flow tuff. In this core, the degree of welding appears to be responsible for most of the variations in porosity, matrix...
Modeling Fluid Flow in Natural Systems, Model Validation and...
media is another important process. The observed relationship between water flux and hydraulic gradient can be highly non-linear. To capture this non-Darcian flow behavior, a new...
NMRI methods for characterizing fluid flow in porous media
Yao, Xiaoli
1997-01-01T23:59:59.000Z
in the measurement and the prediction of flow permeability in rocks. We have investigated the application of Nuclear Magnetic Resonance Imaging to velocity measurement. A stimulated echo pulse field gradient approach was proposed to measure the localized velocity...
Numerical simulation of flow separation control by oscillatory fluid injection
Resendiz Rosas, Celerino
2005-08-29T23:59:59.000Z
In this work, numerical simulations of flow separation control are performed. The sep-aration control technique studied is called 'synthetic jet actuation'. The developed code employs a cell centered finite volume scheme which handles viscous...
Optimal Control of Transient Flow in Natural Gas Networks
Zlotnik, Anatoly; Backhaus, Scott
2015-01-01T23:59:59.000Z
We outline a new control system model for the distributed dynamics of compressible gas flow through large-scale pipeline networks with time-varying injections, withdrawals, and control actions of compressors and regulators. The gas dynamics PDE equations over the pipelines, together with boundary conditions at junctions, are reduced using lumped elements to a sparse nonlinear ODE system expressed in vector-matrix form using graph theoretic notation. This system, which we call the reduced network flow (RNF) model, is a consistent discretization of the PDE equations for gas flow. The RNF forms the dynamic constraints for optimal control problems for pipeline systems with known time-varying withdrawals and injections and gas pressure limits throughout the network. The objectives include economic transient compression (ETC) and minimum load shedding (MLS), which involve minimizing compression costs or, if that is infeasible, minimizing the unfulfilled deliveries, respectively. These continuous functional optimiza...
Magnetohydrodynamic pump with a system for promoting flow of fluid in one direction
Lemoff, Asuncion V. (Union City, CA); Lee, Abraham P. (Irvine, CA)
2010-07-13T23:59:59.000Z
A magnetohydrodynamic pump for pumping a fluid. The pump includes a microfluidic channel for channeling the fluid, a MHD electrode/magnet system operatively connected to the microfluidic channel, and a system for promoting flow of the fluid in one direction in the microfluidic channel. The pump has uses in the medical and biotechnology industries for blood-cell-separation equipment, biochemical assays, chemical synthesis, genetic analysis, drug screening, an array of antigen-antibody reactions, combinatorial chemistry, drug testing, medical and biological diagnostics, and combinatorial chemistry. The pump also has uses in electrochromatography, surface micromachining, laser ablation, inkjet printers, and mechanical micromilling.
Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM
Robinson, Martin; Ramaioli, Marco
2013-01-01T23:59:59.000Z
We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...
Hamel, William R. (Farragut, TN)
1984-01-01T23:59:59.000Z
This invention relates to a new method and new apparatus for determining fluid mass flowrate and density. In one aspect of the invention, the fluid is passed through a straight cantilevered tube in which transient oscillation has been induced, thus generating Coriolis damping forces on the tube. The decay rate and frequency of the resulting damped oscillation are measured, and the fluid mass flowrate and density are determined therefrom. In another aspect of the invention, the fluid is passed through the cantilevered tube while an electrically powered device imparts steady-state harmonic excitation to the tube. This generates Coriolis tube-damping forces which are dependent on the mass flowrate of the fluid. Means are provided to respond to incipient flow-induced changes in the amplitude of vibration by changing the power input to the excitation device as required to sustain the original amplitude of vibration. The fluid mass flowrate and density are determined from the required change in power input. The invention provides stable, rapid, and accurate measurements. It does not require bending of the fluid flow.
Energy of eigen-modes in magnetohydrodynamic flows of ideal fluids
I. V. Khalzov; A. I. Smolyakov; V. I. Ilgisonis
2007-12-11T23:59:59.000Z
Analytical expression for energy of eigen-modes in magnetohydrodynamic flows of ideal fluids is obtained. It is shown that the energy of unstable modes is zero, while the energy of stable oscillatory modes (waves) can assume both positive and negative values. Negative energy waves always correspond to non-symmetric eigen-modes -- modes that have a component of wave-vector along the equilibrium velocity. These results suggest that all non-symmetric instabilities in ideal MHD systems with flows are associated with coupling of positive and negative energy waves. As an example the energy of eigen-modes is calculated for incompressible conducting fluid rotating in axial magnetic field.
Chevarunotai, Natasha
2014-11-13T23:59:59.000Z
calculation. Findings from the sensitivity analysis allow us to make a decision whether or not to acquire more data or to perform additional tests for a more reasonable outcome- the flowing-fluid temperature in the reservoir. Bottomhole flowing...
Medizade, Masoud (San Luis Obispo, CA); Ridgely, John Robert (Los Osos, CA)
2009-12-15T23:59:59.000Z
An arrangement which utilizes an inexpensive flap valve/flow transducer combination and a simple local supervisory control system to monitor and/or control the operation of a positive displacement pump used to extract petroleum from geologic strata. The local supervisory control system controls the operation of an electric motor which drives a reciprocating positive displacement pump so as to maximize the volume of petroleum extracted from the well per pump stroke while minimizing electricity usage and pump-off situations. By reducing the electrical demand and pump-off (i.e., "pounding" or "fluid pound") occurrences, operating and maintenance costs should be reduced sufficiently to allow petroleum recovery from marginally productive petroleum fields. The local supervisory control system includes one or more applications to at least collect flow signal data generated during operation of the positive displacement pump. No flow, low flow and flow duration are easily evaluated using the flap valve/flow transducer arrangement.
A Preliminary Study to Assess Model Uncertainties in Fluid Flows
Delchini, Marc Olivier
2011-08-08T23:59:59.000Z
of the fluid. ? The sound speed, c, is assumed to be constant even if it usually depends on the temperature and the pressure. This is a good approximation for liquids but not for gases. The sound speed is reactor-dependent. ? The Equation Of State (EOS... to the temperature. This parameter is assumed constant in this model. 7 ? ???P is the dilatation of the density due to the pressure. This parameter is also assumed constant but is different for different sound speeds. Its expression is as follows: ?? ?P = 1...
1. INTRODUCTION Fluid flows are often so complicated that laboratory
Nilsson, Johan
with vertical stratification. For a single-hemisphere basin, self-sustained oscillations of the flow and period of the oscillations are partly determined by the energy avail- able for vertical mixing if v, University of Stockholm, Sweden. 4Department of Geosciences, University of Bremen, Germany. 5Climate
Prediction of fluid flow in curved pipe using the finite element method
Maitin, Christopher Benjamin
1987-01-01T23:59:59.000Z
. Therefore mathematical models have been developed to simulate the elfect of these stresses on the flow field. Until recently these models have only been used for simple geometries. With the advancement of the computer, numerical methods have been de... OF SCIENCE May 1987 Major Subject: Mechanical Engineering PREDICTION OF FLUID FLOW IN CURVED PIPE USING THE FINITE ELEMENT METHOD A Thesis CHRISTOPHER B. MAITIN Approved as to style and content by: Dennis L. O'Neal (Chairman of Committee) Warren...
Amber T. Krummel; Sujit S. Datta; Stefan Mnster; David A. Weitz
2013-01-21T23:59:59.000Z
We report an approach to fully visualize the flow of two immiscible fluids through a model three-dimensional (3D) porous medium at pore-scale resolution. Using confocal microscopy, we directly image the drainage of the medium by the non-wetting oil and subsequent imbibition by the wetting fluid. During imbibition, the wetting fluid pinches off threads of oil in the narrow crevices of the medium, forming disconnected oil ganglia. Some of these ganglia remain trapped within the medium. By resolving the full 3D structure of the trapped ganglia, we show that the typical ganglion size, and the total amount of residual oil, decreases as the capillary number Ca increases; this behavior reflects the competition between the viscous pressure in the wetting fluid and the capillary pressure required to force oil through the pores of the medium. This work thus shows how pore-scale fluid dynamics influence the trapped fluid configurations in multiphase flow through 3D porous media.
Device and method for measuring multi-phase fluid flow in a conduit having an abrupt gradual bend
Ortiz, M.G.
1998-02-10T23:59:59.000Z
A system is described for measuring fluid flow in a conduit having an abrupt bend. The system includes pressure transducers, one disposed in the conduit at the inside of the bend and one or more disposed in the conduit at the outside of the bend but spaced a distance therefrom. The pressure transducers measure the pressure of fluid in the conduit at the locations of the pressure transducers and this information is used by a computational device to calculate fluid flow rate in the conduit. For multi-phase fluid, the density of the fluid is measured by another pair of pressure transducers, one of which is located in the conduit elevationally above the other. The computation device then uses the density measurement along with the fluid pressure measurements, to calculate fluid flow. 1 fig.
Paris-Sud XI, Universit de
and the larynx (fig. 1), is the most external part of the respiratory system. Modelling the fluid flow is described. The theory of linear elasticity in small deformations has been chosen to compute the mechanical of the respiratory fluid flow (Shome et al., 1998; Allen et al., 2004; Xu et al., 2006; Sung et al., 2006; Liu et al
GLOBAL OPTIMIZATION OF MULTIPHASE FLOW NETWORKS IN OIL AND GAS PRODUCTION SYSTEMS
Johansen, Tor Arne
1 GLOBAL OPTIMIZATION OF MULTIPHASE FLOW NETWORKS IN OIL AND GAS PRODUCTION SYSTEMS MSc. Hans in an oil production system is developed. Each well may be manipulated by injecting lift gas and adjusting in the maximum oil flow rate, water flow rate, liquid flow rate, and gas flow rate. The wells may also
Shu, Chi-Wang
A conservative Lagrangian scheme for solving compressible fluid flows with multiple internal energy. In some of these ap- plications, multiple internal energy equations such as those for electron, ion developed which are designed to solve the internal energy equation directly. These schemes can be easily
BAYESIAN INFERENCE ON INTEGRATED CONTINUITY FLUID FLOWS AND THEIR APPLICATION TO DUST AEROSOLS
Garbe, Christoph S.
BAYESIAN INFERENCE ON INTEGRATED CONTINUITY FLUID FLOWS AND THEIR APPLICATION TO DUST AEROSOLS Waterloo, Ontario, Canada ABSTRACT The significant role dust aerosols play in the earth's cli- mate system models for aerosol de- tection and atmospheric transport that rely on latent Gaussian Markov random
Boni, Maria
directly from the low-grade metamorphic lithotypes undergoing dolomitization, nor from the low-temperature across large areas of the IglesienteSulcis mining district (SW Sardinia, Italy). The dolomite crops out within circulation cells, which were driven by high heat flow. Fluids originated in the underlying rocks
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow
Wang, Chao-Yang
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow W-dimensional model is developed to simulate discharge of a primary lithium/thionyl chloride battery. The model to the first task with important examples of lead-acid,1-3 nickel-metal hydride,4-8 and lithium-based batteries
Multiphase fluid flow and time lapse UNLP, 11 Octubre de 2012
Santos, Juan
and time lapse seismics p. #12;Introduction. III The analysis of CO2 underground storage safety and time lapse seismics p. #12;Introduction. I Storage of CO2 in geological formations is a procedure project: Sleipner gas field (North Sea). Multiphase fluid flow and time lapse seismics p. #12
Theoretical and Numerical Simulation of Non-Newtonian Fluid Flow in Propped Fractures
Ouyang, Liangchen
2013-12-10T23:59:59.000Z
the original gel. The residual gel exhibits a higher yield stress, and is difficult to remove after fracture closure. But non-Newtonian fluid has complicated rheological equation and its flow behavior in porous media is difficult to be described and modeled...
Fully coupled thermal-mechanical-fluid flow model for nonliner geologic systems
Hart, R.D.
1981-01-01T23:59:59.000Z
A single model is presented which describes fully coupled thermal-mechanical-fluid flow behavior of highly nonlinear, dynamic or quasistatic, porous geologic systems. The mathematical formulation for the model utilizes the continuum theory of mixtures to describe the multiphase nature of the system, and incremental linear constitutive theory to describe the path dependency of nonlinear material behavior. The model, incorporated in an explicit finite difference numerical procedure, was implemented in two different computer codes. A special-purpose one-dimensional code, SNEAKY, was written for initial validation of the coupling mechanisms and testing of the coupled model logic. A general purpose commercially available code, STEALTH, developed for modeling dynamic nonlinear thermomechanical processes, was modified to include fluid flow behavior and the coupling constitutive model. The fully explicit approach in the coupled calculation facilitated the inclusion of the coupling mechanisms and complex constitutive behavior. Analytical solutions pertaining to consolidation theory for soils, thermoelasticity for solids, and hydrothermal convection theory provided verification of stress and fluid flow, stress and conductive heat transfer, and heat transfer and fluid flow couplings, respectively, in the coupled model. A limited validation of the adequacy of the coupling constitutive assumptions was also performed by comparison with the physical response from two laboratory tests. Finally, the full potential of the coupled model is illustrated for geotechnical applications in energy-resource related areas. Examples in the areas of nuclear waste isolation and cut-and-fill mining are cited.
Under consideration for publication in J. Fluid Mech. 1 Analytical studies of flow effects due to
Sen, Mihir
and temporal behaviour of the specific boundary. Steady streaming induced by oscillatory flows over wavy of the wavy surface in comparison to the viscous boundary layer formed over the vibrating wall. Investigating boundaries is presented. A Newtonian viscous fluid confined in an infinite channel with flexible walls
A Numerical Algorithm for Fluid Flow in 3D Naturally Fractured Porous Media
Kentucky, University of
. Such fractured reservoirs could be modeled by permitting the porosity and permeability to vary rapidly as if the reservoir has two porous structures, one for the fractures and the other for the matrix blocksA Numerical Algorithm for Fluid Flow in 3D Naturally Fractured Porous Media Seongjai Kim Abstract
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Boyer, Edmond
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda
Ewing, Richard E.
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda Richard descriptions at various length scales, modeling the effects of this heterogeneity of the porous medium a computer code has been developed which gives concrete quantitative results for the total model, this out
Olshanskii, Maxim A.
with surface tension Kirill D. Nikitin Maxim A. Olshanskii Kirill M. Terekhov Yuri V. Vassilevski§ Abstract to surface tension forces. The method splits one time step into a semi-Lagrangian treatment of the surface models a free surface flow of viscous incompressible fluid subject to surface tension forces. Further
Application of x-ray microtomography to environmental fluid flow D. Wildenschild*a,c
Wildenschild, Dorthe
of fluids in pores ultimately controls subsurface flow and contaminant transport relevant to groundwater-scale measurements make it possible to test existing and new theory, as well as emerging numerical modeling schemes, capillary pressure-saturation relationship 1. INTRODUCTION One of the most difficult and puzzling
CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke
Snooke, Neal
M2 CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke Department- oped on top of the MCIRQ simulator with the aim to produce an automated FMEA for aircraft fuel systems similar to pre- viously developed automated electrical FMEA. Introduction This paper describes a circuit
Dynamics of a confined dusty fluid in a sheared ion flow
Laishram, Modhuchandra; Sharma, Devendra; Kaw, Predhiman K. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)
2014-07-15T23:59:59.000Z
Dynamics of an isothermally driven dust fluid is analyzed which is confined in an azimuthally symmetric cylindrical setup by an effective potential and is in equilibrium with an unconfined sheared flow of a streaming plasma. Cases are analyzed where the confining potential constitutes a barrier for the driven fluid, limiting its spatial extension and boundary velocity. The boundary effects entering the formulation are characterized by applying the appropriate boundary conditions and a range of solutions exhibiting single and multiple vortex are obtained. The equilibrium solutions considered in the cylindrical setup feature a transition from single to multiple vortex state of the driven flow. Effects of (i) the variation in dust viscosity, (ii) coupling between the driving and the driven fluid, and (iii) a friction determining the equilibrium dynamics of the driven system are characterized.
Multiscale Simulation Framework for Coupled Fluid Flow and Mechanical Deformation
Tchelepi, Hamdi
2014-11-14T23:59:59.000Z
A multiscale linear-solver framework for the pressure equation associated with flow in highly heterogeneous porous formations was developed. The multiscale based approach is cast in a general algebraic form, which facilitates integration of the new scalable linear solver in existing flow simulators. The Algebraic Multiscale Solver (AMS) is employed as a preconditioner within a multi-stage strategy. The formulations investigated include the standard MultiScale Finite-Element (MSFE) andMultiScale Finite-Volume (MSFV) methods. The local-stage solvers include incomplete factorization and the so-called Correction Functions (CF) associated with the MSFV approach. Extensive testing of AMS, as an iterative linear solver, indicate excellent convergence rates and computational scalability. AMS compares favorably with advanced Algebraic MultiGrid (AMG) solvers for highly detailed three-dimensional heterogeneous models. Moreover, AMS is expected to be especially beneficial in solving time-dependent problems of coupled multiphase flow and transport in large-scale subsurface formations.
Analysis of fluid flow and heat transfer in a rib grit roughened surface solar air heater using CFD
Karmare, S.V. [Department of Mechanical Engineering, Government College Engineering, Karad 415 124, Maharashtra (India); Shivaji University, Kolhapur, Maharashtra (India); Tikekar, A.N. [Department of Mechanical Engineering, Walchand College of Engineering, Sangli (India); Shivaji University, Kolhapur, Maharashtra (India)
2010-03-15T23:59:59.000Z
This paper presents the study of fluid flow and heat transfer in a solar air heater by using Computational Fluid Dynamics (CFD) which reduces time and cost. Lower side of collector plate is made rough with metal ribs of circular, square and triangular cross-section, having 60 inclinations to the air flow. The grit rib elements are fixed on the surface in staggered manner to form defined grid. The system and operating parameters studied are: e/D{sub h} = 0.044, p/e = 17.5 and l/s = 1.72, for the Reynolds number range 3600-17,000. To validate CFD results, experimental investigations were carried out in the laboratory. It is found that experimental and CFD analysis results give the good agreement. The optimization of rib geometry and its angle of attack is also done. The square cross-section ribs with 58 angle of attack give maximum heat transfer. The percentage enhancement in the heat transfer for square plate over smooth surface is 30%. (author)
Aerodynamic Shape Optimization of Airfoils in Ultra-Low Reynolds Number Flow using
Stanford University
Aerodynamic Shape Optimization of Airfoils in Ultra-Low Reynolds Number Flow using Simultaneous;Aerodynamic Shape Optimization of Airfoils in Ultra-Low Reynolds Number Flow using Simultaneous Pseudo Abstract. The paper presents numerical results of optimized airfoils at ultra-low Reynolds numbers
Flow of mantle fluids through the ductile lower crust: Heliumisotope trends
Kennedy, B. Mack; van Soest, Matthijs C.
2007-10-07T23:59:59.000Z
Heat and mass are injected into the shallow crust when mantle fluids are able to flow through the ductile lower crust. Minimum 3He/4He ratios in surface fluids from the northern Basin and Range province, western North America increase systematically from low, crustal values in the east to high, mantle values in the west, a regional trend that correlates with the rates of active crustal deformation. The highest ratios occur where the extension and shear strain rates are greatest. The correspondence of helium isotope ratios and active trans-tensional deformation indicates a deformation enhanced permeability and that mantle fluids can penetrate the ductile lithosphere in regions even where there is no significant magmatism. Superimposed on the regional trend are local, high-{sup 3}He/{sup 4}He anomalies signifying hidden magmatic activity and/or deep fluid production with locally enhanced permeability, identifying zones with high resource potential, particularly for geothermal energy development.
Multi-objective Optimal Power Flows to Evaluate Voltage Security Costs in Power Networks
Cañizares, Claudio A.
1 Multi-objective Optimal Power Flows to Evaluate Voltage Security Costs in Power Networks William Abstract-- In this paper, new optimal power flow (OPF) tech- niques are proposed based on multi- dard power flow models. The results obtained using the proposed mixed OPFs are compared and analyzed
Toward compressed DMD: spectral analysis of fluid flows using sub-Nyquist-rate PIV data
Tu, Jonathan H; Kutz, J Nathan; Shang, Jessica K
2014-01-01T23:59:59.000Z
Dynamic mode decomposition (DMD) is a powerful and increasingly popular tool for performing spectral analysis of fluid flows. However, it requires data that satisfy the Nyquist-Shannon sampling criterion. In many fluid flow experiments, such data are impossible to capture. We propose a new approach that combines ideas from DMD and compressed sensing. Given a vector-valued signal, we take measurements randomly in time (at a sub-Nyquist rate) and project the data onto a low-dimensional subspace. We then use compressed sensing to identify the dominant frequencies in the signal and their corresponding modes. We demonstrate this method using two examples, analyzing both an artificially constructed test dataset and particle image velocimetry data collected from the flow past a cylinder. In each case, our method correctly identifies the characteristic frequencies and oscillatory modes dominating the signal, proving the proposed method to be a capable tool for spectral analysis using sub-Nyquist-rate sampling.
Simultaneous Extrema in the Entropy Production for Steady-State Fluid Flow in Parallel Pipes
Niven, Robert K
2009-01-01T23:59:59.000Z
Steady-state flow of an incompressible fluid in parallel pipes can simultaneously satisfy two contradictory extremum principles in the entropy production, depending on the flow conditions. For a constant total flow rate, the flow can satisfy (i) a pipe network minimum entropy production (MinEP) principle with respect to the flow rates, and (ii) the maximum entropy production (MaxEP) principle of Paltridge and Ziegler with respect to the choice of flow regime. The first principle - different to but allied to that of Prigogine - arises from the stability of the steady state compared to non-steady-state flows; it is proven for isothermal laminar and turbulent flows in parallel pipes with a constant power law exponent, but is otherwise invalid. The second principle appears to be more fundamental, driving the formation of turbulent flow in single and parallel pipes at higher Reynolds numbers. For constant head conditions, the flow can satisfy (i) a modified maximum entropy production (MaxEPMod) principle of \\v{Z}u...
King, Bradley Donald
2013-12-31T23:59:59.000Z
controlled during calcite precipitation. Ouachita tectonism caused tectonically valved and gravity-driven fluid flow sourced from the Anadarko basin and possibly involved sandstone aquifers or basement. Mechanisms of ancient fluid flow appear to contrast...
Non-Invasive Characterization Of A Flowing Multi-Phase Fluid Using Ultrasonic Interferometry
Sinha, Dipen N. (Los Alamos, NM)
2005-11-01T23:59:59.000Z
An apparatus for noninvasively monitoring the flow and/or the composition of a flowing liquid using ultrasound is described. The position of the resonance peaks for a fluid excited by a swept-frequency ultrasonic signal have been found to change frequency both in response to a change in composition and in response to a change in the flow velocity thereof. Additionally, the distance between successive resonance peaks does not change as a function of flow, but rather in response to a change in composition. Thus, a measurement of both parameters (resonance position and resonance spacing), once calibrated, permits the simultaneous determination of flow rate and composition using the apparatus and method of the present invention.
Armstrong, William D. (Laramie, WY); Naughton, Jonathan (Laramie, WY); Lindberg, William R. (Laramie, WY)
2008-09-02T23:59:59.000Z
A shear stress sensor for measuring fluid wall shear stress on a test surface is provided. The wall shear stress sensor is comprised of an active sensing surface and a sensor body. An elastic mechanism mounted between the active sensing surface and the sensor body allows movement between the active sensing surface and the sensor body. A driving mechanism forces the shear stress sensor to oscillate. A measuring mechanism measures displacement of the active sensing surface relative to the sensor body. The sensor may be operated under periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor measurably changes the amplitude or phase of the motion of the active sensing surface, or changes the force and power required from a control system in order to maintain constant motion. The device may be operated under non-periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor change the transient motion of the active sensor surface or change the force and power required from a control system to maintain a specified transient motion of the active sensor surface.
OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS
Jost O.L. Wendt; Gregory E. Ogden; Jennifer Sinclair; Stephanus Budilarto
2001-09-04T23:59:59.000Z
It is well understood that the stability of axial diffusion flames is dependent on the mixing behavior of the fuel and combustion air streams. Combustion aerodynamic texts typically describe flame stability and transitions from laminar diffusion flames to fully developed turbulent flames as a function of increasing jet velocity. Turbulent diffusion flame stability is greatly influenced by recirculation eddies that transport hot combustion gases back to the burner nozzle. This recirculation enhances mixing and heats the incoming gas streams. Models describing these recirculation eddies utilize conservation of momentum and mass assumptions. Increasing the mass flow rate of either fuel or combustion air increases both the jet velocity and momentum for a fixed burner configuration. Thus, differentiating between gas velocity and momentum is important when evaluating flame stability under various operating conditions. The research efforts described herein are part of an ongoing project directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners. Experimental studies include both cold-and hot-flow evaluations of the following parameters: primary and secondary inlet air velocity, coal concentration in the primary air, coal particle size distribution and flame holder geometry. Hot-flow experiments will also evaluate the effect of wall temperature on burner performance.
Particle-fluid-structure interaction for debris flow impact on flexible barriers
A. Leonardi; F. K. Wittel; M. Mendoza; R. Vetter; H. J. Herrmann
2014-09-29T23:59:59.000Z
Flexible barriers are increasingly used for the protection from debris flow in mountainous terrain due to their low cost and environmental impact. However, a numerical tool for rational design of such structures is still missing. In this work, a hybrid computational framework is presented, using a total Lagrangian formulation of the Finite Element Method (FEM) to represent a flexible barrier. The actions exerted on the structure by a debris flow are obtained from simultaneous simulations of the flow of a fluid-grain mixture, using two conveniently coupled solvers: the Discrete Element Method (DEM) governs the motion of the grains, while the free-surface non-Newtonian fluid phase is solved using the Lattice-Boltzmann Method (LBM). Simulations on realistic geometries show the dependence of the momentum transfer on the barrier on the composition of the debris flow, challenging typical assumptions made during the design process today. In particular, we demonstrate that both grains and fluid contribute in a non-negligible way to the momentum transfer. Moreover, we show how the flexibility of the barrier reduces its vulnerability to structural collapse, and how the stress is distributed on its fabric, highlighting potential weak points.
Nelson, John Stuart (Laguna Niguel, CA); Milner, Thomas Edward (Irvine, CA); Chen, Zhongping (Irvine, CA)
1999-01-01T23:59:59.000Z
Optical Doppler tomography permits imaging of fluid flow velocity in highly scattering media. The tomography system combines Doppler velocimetry with high spatial resolution of partially coherent optical interferometry to measure fluid flow velocity at discrete spatial locations. Noninvasive in vivo imaging of blood flow dynamics and tissue structures with high spatial resolutions of the order of 2 to 10 microns is achieved in biological systems. The backscattered interference signals derived from the interferometer may be analyzed either through power spectrum determination to obtain the position and velocity of each particle in the fluid flow sample at each pixel, or the interference spectral density may be analyzed at each frequency in the spectrum to obtain the positions and velocities of the particles in a cross-section to which the interference spectral density corresponds. The realized resolutions of optical Doppler tomography allows noninvasive in vivo imaging of both blood microcirculation and tissue structure surrounding the vessel which has significance for biomedical research and clinical applications.
Optimal Power Flow of Multiple Energy Carriers(Geidl and Andersson...
system planning The methods used in the paper are linear deterministic system without control signal, optimal power flow and economic dispatch The proposed method stabilized...
Fluid and heat flow in gas-rich geothermal reservoirs
O'Sullivan, M.J.; Bodvarsson, G.S.; Pruess, K.; Blakeley, M.R.
1983-07-01T23:59:59.000Z
Numerical-simulation techniques are used to study the effects of noncondensible gases (CO/sub 2/) on geothermal reservoir behavior in the natural state and during exploitation. It is shown that the presence of CO/sub 2/ has large effects on the thermodynamic conditions of a reservoir in the natural state, especially on temperature distributions and phase compositions. The gas will expand two-phase zones and increase gas saturations to enable flow of CO/sub 2/ through the system. During exploitation, the early pressure drop is primarily due to degassing of the system. This process can cause a very rapid initial pressure drop, on the order of tens of bars, depending upon the initial partial pressure of CO/sub 2/. The following gas content from wells can provide information on in-place gas saturations and relative permeability curves that apply at a given geothermal resource. Site-specific studies are made for the gas-rich two-phase reservoir at the Ohaki geothermal field in New Zealand. A simple lumped-parameter model and a vertical column model are applied to the field data. The results obtained agree well with the natural thermodynamic state of the Ohaki field (pressure and temperature profiles) and a partial pressure of 15 to 25 bars is calculated in the primary reservoirs. The models also agree reasonably well with field data obtained during exploitation of the field. The treatment of thermophysical properties of H/sub 2/O-CO/sub 2/ mixtures for different phase compositions is summarized.
Volume-averaged macroscopic equation for fluid flow in moving porous media
Wang, Liang; Guo, Zhaoli; Mi, Jianchun
2014-01-01T23:59:59.000Z
Darcy's law and the Brinkman equation are two main models used for creeping fluid flows inside moving permeable particles. For these two models, the time derivative and the nonlinear convective terms of fluid velocity are neglected in the momentum equation. In this paper, a new momentum equation including these two terms are rigorously derived from the pore-scale microscopic equations by the volume-averaging method, which can reduces to Darcy's law and the Brinkman equation under creeping flow conditions. Using the lattice Boltzmann equation method, the macroscopic equations are solved for the problem of a porous circular cylinder moving along the centerline of a channel. Galilean invariance of the equations are investigated both with the intrinsic phase averaged velocity and the phase averaged velocity. The results demonstrate that the commonly used phase averaged velocity cannot serve as the superficial velocity, while the intrinsic phase averaged velocity should be chosen for porous particulate systems.
TOUGH Simulations of the Updegraff's Set of Fluid and Heat Flow Problems
Moridis, G.J.; Pruess (editor), K.
1992-11-01T23:59:59.000Z
The TOUGH code [Pruess, 1987] for two-phase flow of water, air, and heat in penneable media has been exercised on a suite of test problems originally selected and simulated by C. D. Updegraff [1989]. These include five 'verification' problems for which analytical or numerical solutions are available, and three 'validation' problems that model laboratory fluid and heat flow experiments. All problems could be run without any code modifications (*). Good and efficient numerical performance, as well as accurate results were obtained throughout. Additional code verification and validation problems from the literature are briefly summarized, and suggestions are given for proper applications of TOUGH and related codes.
Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs
Maria Cecilia Bravo
2006-06-30T23:59:59.000Z
This document reports progress of this research effort in identifying relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. These dependencies are investigated by identifying the main transport mechanisms at the pore scale that should affect fluids flow at the reservoir scale. A critical review of commercial reservoir simulators, used to predict tight sand gas reservoir, revealed that many are poor when used to model fluid flow through tight reservoirs. Conventional simulators ignore altogether or model incorrectly certain phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization. We studied the effect of Knudsen's number in Klinkenberg's equation and evaluated the effect of different flow regimes on Klinkenberg's parameter b. We developed a model capable of explaining the pressure dependence of this parameter that has been experimentally observed, but not explained in the conventional formalisms. We demonstrated the relevance of this, so far ignored effect, in tight sands reservoir modeling. A 2-D numerical simulator based on equations that capture the above mentioned phenomena was developed. Dynamic implications of new equations are comprehensively discussed in our work and their relative contribution to the flow rate is evaluated. We performed several simulation sensitivity studies that evidenced that, in general terms, our formalism should be implemented in order to get more reliable tight sands gas reservoirs' predictions.
Fluid flow release regulating device, ERIP {number_sign}624: Final report
NONE
1997-12-01T23:59:59.000Z
DOE/ERIP project {number_sign}624 ``Fluid Flow Release Regulating Device`` designed, constructed, tested, and installed a rubber crest gate for regulating water levels at an impoundment such as a hydroelectric dam. A 92 foot long by 27 inch high rubber panel was installed in January 1997. Initial results were good until fabric degradation internal to the rubber caused loss of stiffness. Substitutes for the failed fabric are being tested. The project will continue after DOE participation terminates.
STRUCTURAL HETEROGENEITIES AND PALEO FLUID FLOW IN AN ANALOG SANDSTONE RESERVOIR 2001-2004
Pollard, David; Aydin, Atilla
2005-02-22T23:59:59.000Z
Fractures and faults are brittle structural heterogeneities that can act both as conduits and barriers with respect to fluid flow in rock. This range in the hydraulic effects of fractures and faults greatly complicates the challenges faced by geoscientists working on important problems: from groundwater aquifer and hydrocarbon reservoir management, to subsurface contaminant fate and transport, to underground nuclear waste isolation, to the subsurface sequestration of CO2 produced during fossil-fuel combustion. The research performed under DOE grant DE-FG03-94ER14462 aimed to address these challenges by laying a solid foundation, based on detailed geological mapping, laboratory experiments, and physical process modeling, on which to build our interpretive and predictive capabilities regarding the structure, patterns, and fluid flow properties of fractures and faults in sandstone reservoirs. The material in this final technical report focuses on the period of the investigation from July 1, 2001 to October 31, 2004. The Aztec Sandstone at the Valley of Fire, Nevada, provides an unusually rich natural laboratory in which exposures of joints, shear deformation bands, compaction bands and faults at scales ranging from centimeters to kilometers can be studied in an analog for sandstone aquifers and reservoirs. The suite of structures there has been documented and studied in detail using a combination of low-altitude aerial photography, outcrop-scale mapping and advanced computational analysis. In addition, chemical alteration patterns indicative of multiple paleo fluid flow events have been mapped at outcrop, local and regional scales. The Valley of Fire region has experienced multiple episodes of fluid flow and this is readily evident in the vibrant patterns of chemical alteration from which the Valley of Fire derives its name. We have successfully integrated detailed field and petrographic observation and analysis, process-based mechanical modeling, and numerical simulation of fluid flow to study a typical sandstone aquifer/reservoir at a variety of scales. We have produced many tools and insights which can be applied to active subsurface flow systems and practical problems of pressing global importance.
Transient fluid and heat flow modeling in coupled wellbore/reservoir systems
Izgec, Bulent
2009-05-15T23:59:59.000Z
....................................................... 66 5.3.1 Modeling Field Data ..................................................................... 68 5.3.2 Optimal Location of Permanent Downhole Gauge....................... 71 5.4 Effect of Gauge Location on Pressure-Transient Analysis... at the midpoint of the flow string................................. 70 Figure 5.26 Downhole gauge placement configurations .............................................. 71 Figure 5.27 Temperature and density profiles in the wellbore...
Numerical method for fluid flow and heat transfer in magnetohydrodynamic flow
Kim, C.N.; Abdou, M.A.
1989-03-01T23:59:59.000Z
A new numerical algorithm was developed to provide a fully detailed flow field in liquid metal MHD flow with a relatively large Hartmann number and interaction parameter. The algorithm includes the effects of advection and diffusion, and is capable of predicting momentum and heat transfer in MHD flows. Using this algorithm, an incompressible, viscous, three-dimensional MHD flow in a square duct is investigated at a low magnetic Reynolds number by means of the finite volume method. The velocity and temperature profiles are obtained in the developing region for constant wall temperature. The result shows that large velocities are obtained near the insulating walls parallel to the magnetic field. Also, near the perfectly conducting walls perpendicular to the field, a velocity profile like a Hartmann layer is obtained. In association with the velocity profiles, Nusselt number at the insulating walls (with side layer) is seen to be larger than that at the perfectly conducting walls (with Hartmann layer).
An Optimal Power Flow (OPF) Method with Improved Power System Stability
Chen, Zhe
An Optimal Power Flow (OPF) Method with Improved Power System Stability Chi Su, Zhe Chen Department corresponding to certain critical oscillation modes. Power system stabilizer (PSS) and thyristor controlled an optimal power flow (OPF) method taking into account small signal stability as additional constraints
Stability-Constrained Optimal Power Flow and Its Application to Pricing Power System Stabilizers
Caizares, Claudio A.
1 Stability-Constrained Optimal Power Flow and Its Application to Pricing Power System Stabilizers locational marginal prices. A power system stabilizer (PSS) is then introduced in the test system Terms-- Angle stability, power system oscillations, elec- tricity markets, optimal power flow
Bertsekas, Dimitri
-switched network. We discuss an integer-linear programming formulation, which can be addressed with highly efficient linear (not integer) programming methods, to obtain optimal or nearly optimal solutions. 1 multicommodity flow problems. We focus in particular on the problem of routing and wavelength assignment (RWA
Haghshenas, Arash
2013-04-24T23:59:59.000Z
The worst scenario of drilling operation is blowout which is uncontrolled flow of formation fluid into the wellbore. Blowouts result in environmental damage with potential risk of injuries and fatalities. Although not all ...
The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc
Glasgow, University of
The influence of fluid flow through granitic crust: a thermo-tectonic study in and on Mont Blanc Tim Dempster, Cristina Persano and Zoe Shipton *Tim.Dempster@ges.gla.ac.uk Granitic and gneissose within a evolving mountain zone, the metasomatic influence of fluids in granite gneiss and the resulting
Continuum-particle hybrid coupling for mass, momentum and energy transfers in unsteady fluid flow
R. Delgado-Buscalioni; P. V. Coveney
2003-02-25T23:59:59.000Z
The aim of hybrid methods in simulations is to communicate regions with disparate time and length scales. Here, a fluid described at the atomistic level within an inner region P is coupled to an outer region C described by continuum fluid dynamics. The matching of both descriptions of matter is made across an overlapping region and, in general, consists of a two-way coupling scheme (C->P and P->C) which conveys mass, momentum and energy fluxes. The contribution of the hybrid scheme hereby presented is two-fold: first it treats unsteady flows and, more importantly, it handles energy exchange between both C and P regions. The implementation of the C->P coupling is tested here using steady and unsteady flows with different rates of mass, momentum and energy exchange. In particular, relaxing flows described by linear hydrodynamics (transversal and longitudinal waves) are most enlightening as they comprise the whole set of hydrodynamic modes. Applying the hybrid coupling scheme after the onset of an initial perturbation, the cell-averaged Fourier components of the flow variables in the P region (velocity, density, internal energy, temperature and pressure) evolve in excellent agreement with the hydrodynamic trends. It is also shown that the scheme preserves the correct rate of entropy production. We discuss some general requirements on the coarse-grained length and time scales arising from both the characteristic microscopic and hydrodynamic scales.
Harstad, H. [New Mexico Tech, Socorro, NM (United States); Teufel, L.W.; Lorenz, J.C.; Brown, S.R. [Sandia National Labs., Albuquerque, NM (United States). Geomechanics Dept.
1996-08-01T23:59:59.000Z
Significant gas reserves are present in low-permeability sandstones of the Frontier Formation in the greater Green River Basin, Wyoming. Successful exploitation of these reservoirs requires an understanding of the characteristics and fluid-flow response of the regional natural fracture system that controls reservoir productivity. Fracture characteristics were obtained from outcrop studies of Frontier sandstones at locations in the basin. The fracture data were combined with matrix permeability data to compute an anisotropic horizontal permeability tensor (magnitude and direction) corresponding to an equivalent reservoir system in the subsurface using a computational model developed by Oda (1985). This analysis shows that the maximum and minimum horizontal permeability and flow capacity are controlled by fracture intensity and decrease with increasing bed thickness. However, storage capacity is controlled by matrix porosity and increases linearly with increasing bed thickness. The relationship between bed thickness and the calculated fluid-flow properties was used in a reservoir simulation study of vertical, hydraulically-fractured and horizontal wells and horizontal wells of different lengths in analogous naturally fractured gas reservoirs. The simulation results show that flow capacity dominates early time production, while storage capacity dominates pressure support over time for vertical wells. For horizontal wells drilled perpendicular to the maximum permeability direction a high target production rate can be maintained over a longer time and have higher cumulative production than vertical wells. Longer horizontal wells are required for the same cumulative production with decreasing bed thickness.
Donald M. McEligot; Stefan Becker; Hugh M. McIlroy, Jr.
2010-07-01T23:59:59.000Z
In recent international collaboration, INL and Uni. Erlangen have developed large MIR flow systems which can be ideal for joint graduate student education and research. The benefit of the MIR technique is that it permits optical measurements to determine flow characteristics in complex passages and around objects to be obtained without locating a disturbing transducer in the flow field and without distortion of the optical paths. The MIR technique is not new itself; others employed it earlier. The innovation of these MIR systems is their large size relative to previous experiments, yielding improved spatial and temporal resolution. This report will discuss the benefits of the technique, characteristics of the systems and some examples of their applications to complex situations. Typically their experiments have provided new fundamental understanding plus benchmark data for assessment and possible validation of computational thermal fluid dynamic codes.
Marisetti, Sudheer N
1990-01-01T23:59:59.000Z
the implementation of a, combined flow control and optimal routing algorithm in packet switched networks. In addition, we study the influence of various objective functions on maximum link utilization, average packet delay, and fairness, The algorithm is based... on the gradient projection method. Flow control is introduced through fictituous links that connect origins to destinations and carry the rejected load. The fictitious links reduce the problem of combined routing and flow control to the optimal routing problem...
Obied Allah, M. H. [Department of Mathematics, Faculty of Science, Assiut University, Assiut (Egypt)
2013-04-15T23:59:59.000Z
In this work, a viscous potential flow analysis is used to investigate capillary surface waves between two horizontal finite fluid layers. The two layers have finite conductivities and admit mass and heat transfer. A general dispersion relation is derived. The presence of finite conductivities together with the dielectric permeabilities makes the horizontal electric field play a dual role in the stability criterion. The phenomenon of negative viscosity is observed. A new growth rate parameter, depending on the kinematical viscosity of the lower fluid layer, is found and has a stabilizing effect on the unstable modes. The growth rates and neutral stability curve are given and applied to air-water interface. The effects of various parameters are discussed for the Kelvin-Helmholtz and the Rayleigh-Taylor instabilities.
TOUGH2: A general-purpose numerical simulator for multiphase fluid and heat flow
Pruess, K.
1991-05-01T23:59:59.000Z
TOUGH2 is a numerical simulation program for nonisothermal flows of multicomponent, multiphase fluids in porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, and unsaturated zone hydrology. A successor to the TOUGH program, TOUGH2 offers added capabilities and user features, including the flexibility to handle different fluid mixtures, facilities for processing of geometric data (computational grids), and an internal version control system to ensure referenceability of code applications. This report includes a detailed description of governing equations, program architecture, and user features. Enhancements in data inputs relative to TOUGH are described, and a number of sample problems are given to illustrate code applications. 46 refs., 29 figs., 12 tabs.
Elmroth, Erik
A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat groundwater flow related problems such as nuclear waste isolation, environmental remediation, and geothermal with blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid partitioning
Elmroth, Erik
A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat groundwater flow related problems such as nuclear waste isolation, environmental remediation, and geothermal 6 blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid
Multiphase Fluid Flow in Deformable Variable-Aperture Fractures - Final Report
Detwiler, Russell
2014-04-30T23:59:59.000Z
Fractures provide flow paths that can potentially lead to fast migration of fluids or contaminants. A number of energy-?related applications involve fluid injections that significantly perturb both the pressures and chemical composition of subsurface fluids. These perturbations can cause both mechanical deformation and chemical alteration of host rocks with potential for significant changes in permeability. In fractured rock subjected to coupled chemical and mechanical stresses, it can be difficult to predict the sign of permeability changes, let alone the magnitude. This project integrated experimental and computational studies to improve mechanistic understanding of these coupled processes and develop and test predictive models and monitoring techniques. The project involved three major components: (1) study of two-?phase flow processes involving mass transfer between phases and dissolution of minerals along fracture surfaces (Detwiler et al., 2009; Detwiler, 2010); (2) study of fracture dissolution in fractures subjected to normal stresses using experimental techniques (Ameli, et al., 2013; Elkhoury et al., 2013; Elkhoury et al., 2014) and newly developed computational models (Ameli, et al., 2014); (3) evaluation of electrical resistivity tomography (ERT) as a method to detect and quantify gas leakage through a fractured caprock (Breen et al., 2012; Lochbuhler et al., 2014). The project provided support for one PhD student (Dr. Pasha Ameli; 2009-?2013) and partially supported a post-?doctoral scholar (Dr. Jean Elkhoury; 2010-?2013). In addition, the project provided supplemental funding to support collaboration with Dr. Charles Carrigan at Lawrence Livermore National Laboratory in connection with (3) and supported one MS student (Stephen Breen; 2011-?2013). Major results from each component of the project include the following: (1) Mineral dissolution in fractures occupied by two fluid phases (e.g., oil-?water or water-?CO{sub 2}) causes changes in local capillary forces and redistribution of fluids. These coupled processes enhance channel formation and the potential for development of fast flow paths through fractures. (2) Dissolution in fractures subjected to normal stress can result in behaviors ranging from development of dissolution channels and rapid permeability increases to fracture healing and significant permeability decreases. The timescales associated with advective transport of dissolved ions in the fracture, mineral dissolution rates, and diffusion within the adjacent porous matrix dictate the sign and magnitude of the resulting permeability changes. Furthermore, a high-? resolution mechanistic model that couples elastic deformation of contacts and aperture-?dependent dissolution rates predicts the range of observed behaviors reasonably well. (3) ERT has potential as a tool for monitoring gas leakage in deep formations. Using probabilistic inversion methods further enhances the results by providing uncertainty estimates of inverted parameters.
Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model
Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)
2010-12-23T23:59:59.000Z
Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.
is a technique used to image the volume of rock stimulated by hydraulic fracturing (Al- bright and Pearson, 1982. The method has been applied in devel- oping hot dry rock reservoirs (e.g., Pine and Batchelor, 1984; House al., 2003). Beyond mapping gross structure and fluid-flow paths, rela- tive source location
Bukhsh, Waqquas Ahmed
2014-07-01T23:59:59.000Z
Optimization plays a central role in the control and operation of electricity power networks. In this thesis we focus on two very important optimization problems in power systems. The first is the optimal power flow ...
The Properties of Confined Water and Fluid Flow at the Nanoscale
Schwegler, E; Reed, J; Lau, E; Prendergast, D; Galli, G; Grossman, J C; Cicero, G
2009-03-09T23:59:59.000Z
This project has been focused on the development of accurate computational tools to study fluids in confined, nanoscale geometries, and the application of these techniques to probe the structural and electronic properties of water confined between hydrophilic and hydrophobic substrates, including the presence of simple ions at the interfaces. In particular, we have used a series of ab-initio molecular dynamics simulations and quantum Monte Carlo calculations to build an understanding of how hydrogen bonding and solvation are modified at the nanoscale. The properties of confined water affect a wide range of scientific and technological problems - including protein folding, cell-membrane flow, materials properties in confined media and nanofluidic devices.
A photographic study of fluid flow theory for two-dimensional laminar flow around solid bodies
Lee, Wen Ho
1966-01-01T23:59:59.000Z
Table 2. Mater Table, a Bottom View 3. A Top View of Water Table 4. A View of the Mhole Equipment 5. Dimensions of the Mater Table 6. Copper Tank and Rubber Bodies 7. Diagram oi' Stream Velocity H. Diagram of Stream Function 9. Diagram of grad P... 22. Source with Strength 0 = 5 in /min 3 23. Source with Strength Q - 10 in /min 24. The Streamlines of' Figure 22 25. The StreamC. ines of' Figure 23 26. Rectilinear Flow with U 0. 08 f't/sec around an 25 26 26 27 27 28 Airfoil with Angle...
Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing
Freifeld, B.; Finsterle, S.
2010-12-10T23:59:59.000Z
The objective of Task 2 is to develop a numerical method for the efficient and accurate analysis of distributed thermal perturbation sensing (DTPS) data for (1) imaging flow profiles and (2) in situ determination of thermal conductivities and heat fluxes. Numerical forward and inverse modeling is employed to: (1) Examine heat and fluid flow processes near a geothermal well under heating and cooling conditions; (2) Demonstrate ability to interpret DTPS thermal profiles with acceptable estimation uncertainty using inverse modeling of synthetic temperature data; and (3) Develop template model and analysis procedure for the inversion of temperature data collected during a thermal perturbation test using fiber-optic distributed temperature sensors. This status report summarizes initial model developments and analyses.
Fuel cell assembly fluid flow plate having conductive fibers and rigidizing material therein
Walsh, Michael M. (Fairfield, CT)
2000-01-01T23:59:59.000Z
A fluid flow plate is preferably formed with three initial sections, for instance, two layers of conductive (e.g., metal) fibers and a barrier material (e.g., metal foil) which is interposed between the two layers. For example, sintering of these three sections can provide electrical path(s) between outer faces of the two layers. Then, the sintered sections can be, for instance, placed in a mold for forming of flow channel(s) into one or more of the outer faces. Next, rigidizing material (e.g., resin) can be injected into the mold, for example, to fill and/or seal space(s) about a conductive matrix of the electrical path(s). Preferably, abrading of surface(s) of the outer face(s) serves to expose electrical contact(s) to the electrical path(s).
de Stadler, M; Chand, K
2007-11-12T23:59:59.000Z
Gas centrifuges exhibit very complex flows. Within the centrifuge there is a rarefied region, a transition region, and a region with an extreme density gradient. The flow moves at hypersonic speeds and shock waves are present. However, the flow is subsonic in the axisymmetric plane. The analysis may be simplified by treating the flow as a perturbation of wheel flow. Wheel flow implies that the fluid is moving as a solid body. With the very large pressure gradient, the majority of the fluid is located very close to the rotor wall and moves at an azimuthal velocity proportional to its distance from the rotor wall; there is no slipping in the azimuthal plane. The fluid can be modeled as incompressible and subsonic in the axisymmetric plane. By treating the centrifuge as long, end effects can be appropriately modeled without performing a detailed boundary layer analysis. Onsager's pancake approximation is used to construct a simulation to model fluid flow in a gas centrifuge. The governing 6th order partial differential equation is broken down into an equivalent coupled system of three equations and then solved numerically. In addition to a discussion on the baseline solution, known problems and future work possibilities are presented.
An overview of instability and fingering during immiscible fluid flow in porous and fractured media
Chen, G.; Neuman, S.P. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Hydrology and Water Resources; Taniguchi, M. [Nara Univ. of Education (Japan). Dept. of Earth Sciences
1995-04-01T23:59:59.000Z
Wetting front instability is an important phenomenon affecting fluid flow and contaminant transport in unsaturated soils and rocks. It causes the development of fingers which travel faster than would a uniform front and thus bypass much of the medium. Water saturation and solute concentration in such fingers tend to be higher than in the surrounding medium. During infiltration, fingering may cause unexpectedly rapid arrival of water and solute at the water-table. This notwithstanding, most models of subsurface flow and transport ignore instability and fingering. In this report, we survey the literature to assess the extent to which this may or may not be justified. Our overview covers experiments, theoretical studies, and computer simulations of instability and fingering during immiscible two-phase flow and transport, with emphasis on infiltration into soils and fractured rocks. Our description of instability in an ideal fracture (Hele-Shaw cell) includes an extension of existing theory to fractures and interfaces having arbitrary orientations in space. Our discussion of instability in porous media includes a slight but important correction of existing theory for the case of an inclined interface. We conclude by outlining some potential directions for future research. Among these, we single out the effect of soil and rock heterogeneities on instability and preferential flow as meriting special attention in the context of nuclear waste storage in unsaturated media.
High-heat-flux removal by phase-change fluid and particulate flow
Gorbis, Z.R.; Raffray, A.R.; Abdou, M.A. (Univ. of California, Los Angeles (United States))
1993-07-01T23:59:59.000Z
A new concept based on particulate flow in which either or both the particulates and the fluid could undergo phase changes is proposed. The presence of particulates provides not only a mechanism for additional heat removal through phase change but also the potential for increasing the rate of heat transfer by enhancing convection through surface region/bulk [open quotes]mixing[close quotes], by enhancing radiation, particularly for high-temperature cases; and for the case of multiphase fluid, by enhancing the boiling process. One particularly interesting coolant system based on this concept is [open quotes]subcooled boiling water-ice particulate[close quotes] flow. A preliminary analysis of this coolant system is presented, the results of which indicate that such a coolant system is better applied for cooling of relatively small surface areas with high local heat fluxes, where a conventional cooling system would come short of providing the required heat removal at acceptable coolant pressure levels. 14 refs., 8 figs.
Structure-exploiting interior point methods for security constrained optimal power flow problems
Chiang, Naiyuan
2013-07-01T23:59:59.000Z
The aim of this research is to demonstrate some more efficient approaches to solve the n-1 security constrained optimal power flow (SCOPF) problems by using structure-exploiting primal-dual interior point methods ...
Moller, Nancy; Weare J. H.
2008-05-29T23:59:59.000Z
Successful exploitation of the vast amount of heat stored beneath the earths surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nations domestic energy inventory and thereby promote a more secure energy supply, a stronger economy and a cleaner environment. However, a major factor limiting the expanded development of current hydrothermal resources as well as the production of enhanced geothermal systems (EGS) is insufficient knowledge about the chemical processes controlling subsurface fluid flow. With funding from past grants from the DOE geothermal program and other agencies, we successfully developed advanced equation of state (EOS) and simulation technologies that accurately describe the chemistry of geothermal reservoirs and energy production processes via their free energies for wide XTP ranges. Using the specific interaction equations of Pitzer, we showed that our TEQUIL chemical models can correctly simulate behavior (e.g., mineral scaling and saturation ratios, gas break out, brine mixing effects, down hole temperatures and fluid chemical composition, spent brine incompatibilities) within the compositional range (Na-K-Ca-Cl-SO4-CO3-H2O-SiO2-CO2(g)) and temperature range (T < 350C) associated with many current geothermal energy production sites that produce brines with temperatures below the critical point of water. The goal of research carried out under DOE grant DE-FG36-04GO14300 (10/1/2004-12/31/2007) was to expand the compositional range of our Pitzer-based TEQUIL fluid/rock interaction models to include the important aluminum and silica interactions (T < 350C). Aluminum is the third most abundant element in the earths crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earths crust. The ability to accurately characterize effects of temperature, fluid mixing and interactions between major rock-forming minerals and hydrothermal and/or injected fluids is critical to predict important chemical behaviors affecting fluid flow, such as mineral precipitation/dissolution reactions. We successfully achieved the project goal and objectives by demonstrating the ability of our modeling technology to correctly predict the complex pH dependent solution chemistry of the Al3+ cation and its hydrolysis species: Al(OH)2+, Al(OH)2+, Al(OH)30, and Al(OH)4- as well as the solubility of common aluminum hydroxide and aluminosilicate minerals in aqueous brines containing components (Na, K, Cl) commonly dominating hydrothermal fluids. In the sodium chloride system, where experimental data for model parameterization are most plentiful, the model extends to 300C. Determining the stability fields of aluminum species that control the solubility of aluminum-containing minerals as a function of temperature and composition has been a major objective of research in hydrothermal chemistry.
Spane, Frank A.
2013-04-29T23:59:59.000Z
Preliminary Analysis of Grande Ronde Basalt Formation Flow Top Transmissivity as it Relates to Assessment and Site Selection Applications for Fluid/Energy Storage and Sequestration Projects
A Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization
Coello, Carlos A. Coello
that the correct- ness of algebraic transformations realized by the underlying genetic operators selection shown for power optimization. In order to avoid inferior results caused by the counteracting demandsA Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization Birger Landwehr
Jacobian Singularities in Optimal Power Flow Problems Caused by Intertemporal Constraints
Li, Xin
that are time-dependent such as generator ramp limits and specifically energy storage constraints may cause on the Newton-Raphson al- gorithm are widely used to solve Optimal Power Flow (OPF) and Economic Dispatch a storage device is integrated into a multi-timestep OPF problem and the optimal solution
1464 IEEE TRANSACTIONS ON SMART GRID, VOL. 4, NO. 3, SEPTEMBER 2013 Distributed Optimal Power Flow
Giannakis, Georgios
--Distributed optimization, distribution feeders, microgrids, optimal power flow, semidefinite relaxation. I. INTRODUCTION MICROGRIDS are portions of a power distribution net- work located downstream of the distribution substation) and energy storage devices [1]. A microgrid can operate in either grid-connected, islanded, or hybrid modes
U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers
Maher, Kate; DePaolo, Donald J.; Christensen, John N.
2005-12-27T23:59:59.000Z
Both chemical weathering rates and fluid flow are difficultto measure in natural systems. However, these parameters are critical forunderstanding the hydrochemical evolution of aquifers, predicting thefate and transport of contaminants, and for water resources/water qualityconsiderations. 87Sr/86Sr and (234U/238U) activity ratios are sensitiveindicators of water-rock interaction, and thus provide a means ofquantifying both flow and reactivity. The 87Sr/86Sr values in groundwaters are controlled by the ratio of the dissolution rate to the flowrate. Similarly, the (234U/238U) ratio of natural ground waters is abalance between the flow rate and the dissolution of solids, andalpha-recoil loss of 234U from the solids. By coupling these two isotopesystems it is possible to constrain both the long-term (ca. 100's to1000's of years) flow rate and bulk dissolution rate along the flow path.Previous estimates of the ratio of the dissolution rate to theinfiltration flux from Sr isotopes (87Sr/86Sr) are combined with a modelfor (234U/238U) to constrain the infiltration flux and dissolution ratefor a 70-m deep vadose zone core from Hanford, Washington. The coupledmodel for both (234U/238U) ratios and the 87Sr/86Sr data suggests aninfiltration flux of 5+-2 mm/yr, and bulk silicate dissolution ratesbetween 10-15.7 and 10-16.5 mol/m2/s. The process of alpha-recoilenrichment, while primarily responsible for the observed variation in(234U/238U) of natural systems, is difficult to quantify. However, therate of this process in natural systems affects the interpretation ofmost U-series data. Models for quantifying the alpha-recoil loss fractionbased on geometric predictions, surface area constraints, and chemicalmethods are also presented. The agreement between the chemical andtheoretical methods, such as direct measurement of (234U/238U) of thesmall grain size fraction and geometric calculations for that sizefraction, is quite good.
Edinburgh Research Explorer Local solutions of the optimal power flow problem
Millar, Andrew J.
law (KVL), which describes the flow of power in transmission lines, and is a nonlinear function of bus is to find a steady state operating point that minimizes the cost of electric power generation whileEdinburgh Research Explorer Local solutions of the optimal power flow problem Citation
Outage Detection in Power Distribution Networks with Optimally-Deployed Power Flow Sensors
Zhao, Yue
Outage Detection in Power Distribution Networks with Optimally-Deployed Power Flow Sensors Yue Zhao deployed real-time power flow sensors and that of load estimates via Advanced Metering Infrastructure (AMI of Naval Research, under Grant N00014-12-1-0767. where supervisory control and data acquisition (SCADA
Lopez, Jose M; Avila, Marc
2015-01-01T23:59:59.000Z
The flow of fluid confined between a heated rotating cylinder and a cooled stationary cylinder is a canonical experiment for the study of heat transfer in engineering. The theoretical treatment of this system is greatly simplified if the cylinders are assumed to be of infinite length or periodic in the axial direction, in which cases heat transfer occurs only through conduction as in a solid. We here investigate numerically heat transfer and the onset of turbulence in such flows by using both periodic and no-slip boundary conditions in the axial direction. We obtain a simple linear criterion that determines whether the infinite-cylinder assumption can be employed. The curvature of the cylinders enters this linear relationship through the slope and additive constant. For a given length-to-gap aspect ratio there is a critical Rayleigh number beyond which the laminar flow in the finite system is convective and so the behaviour is entirely different from the periodic case. The criterion does not depend on the Pra...
Measurement of fluid-flow-velocity profile in turbid media by the use of optical Doppler tomography
Wang, Xiao-Jun; Milner, T.E.; Chen, Zhongping; Nelson, J.S. [Beckman Laser Institute and Medical Clinic, University of California-Irvine, Irvine, California 92715 (United States)]|[Department of Physics, Georgia Southern University, Statesboro, Georgia 30460 (United States)
1997-01-01T23:59:59.000Z
Optical Doppler tomography is demonstrated to be a simple, accurate, and noncontact method for measuring the fluid velocity of laminar flow in small-diameter ({approximately}0.5-mm) ducts. Studies are described that utilize circular (square) plastic (glass) ducts infused with a moving suspension of polymer micro-spheres in air and buried in an optically turbid medium. The measurement of Doppler-shifted frequencies of backscattered light from moving microspheres is used to construct a high-resolution spatial profile of fluid-flow velocity in the ducts. {copyright} 1997 Optical Society of America
Etheridge, William B. (William Bruce)
2007-01-01T23:59:59.000Z
An experimental study was undertaken to investigate if a loosely-packed particle layer can induce mixing due to diffusion-driven Phillips-Wunsch boundary flows in a quiescent stratified fluid. Diffusion-driven flows can ...
European Journal of Mechanics B/Fluids 25 (2006) 9871007 Wave propagation in a fluid flowing through
Pontrelli, Giuseppe
2006-01-01T23:59:59.000Z
oscillatory flow has been considered in many studies. This work was initiated by Lyne [5] who used boundary-layer
MINET: transient analysis of fluid-flow and heat-transfer networks
Van Tuyle, G.J.; Guppy, J.G.; Nepsee, T.C.
1983-01-01T23:59:59.000Z
MINET, a computer code developed for the steady-state and transient analysis of fluid-flow and heat-transfer networks, is described. The code is based on a momentum integral network method, which offers significant computational advantages in the analysis of large systems, such as the balance of plant in a power-generating facility. An application is discussed in which MINET is coupled to the Super System Code (SSC), an advanced generic code for the transient analysis of loop- or pool-type LMFBR systems. In this application, the ability of the Clinch River Breeder Reactor Plant to operate in a natural circulation mode following an assumed loss of all electric power, was assessed. Results from the MINET portion of the calculations are compared against those generated independently by the Clinch River Project, using the DEMO code.
Flow control optimization in a jet engine serpentine inlet duct
Kumar, Abhinav
2009-05-15T23:59:59.000Z
Computational investigations were carried out on an advanced serpentine jet engine inlet duct to understand the development and propagation of secondary flow structures. Computational analysis which went in tandem with experimental investigation...
One Time-step Finite Element Discretization of the Equation of Motion of Two-fluid Flows
Maury, Bertrand
obtained at each time step when dis- cretizing the lubricated transportation of heavy crude oil in a horizontal pipeline. In the petroleum industry, an efficient way for transporting heavy crude oil to the pipe wall and it surrounds the fluid with high viscosity (heavy oil). It is assumed that the flow
Chen, Qingyan "Yan"
Fast and Informative Flow Simulations in a Building by Using Fast Fluid Dynamics Model on Graphics solve Navier-Stokes equations and other transportation equations for energy and species at a speed of 50 it in parallel on a Graphics Processing Unit (GPU). This study validated the FFD on the GPU by simulating
Bier, Martin
will show that a sufficiently large boundary vor- ticity layer is required for stationary vortices and that a suf- ficiently high Reynolds number with a boundary shear stress is required for traveling oscillatoryStable stationary vortices and traveling oscillatory vortices in a stenotic fluid-flow channel
Method and apparatus for balancing discharge fluid flow in drilling mud treatment units
Gay, C.J.
1983-03-29T23:59:59.000Z
A method of controlling fluid flow in the drilling mud treatment units of an oil/gas well drilling rig such as, for example, the shale shaker, desander, desilter, and mud cleaner portions thereof provides floating the inlet of an intake conduit at the supernatent liquid layer of the drilling rig reserve pit and providing a common distributor head for routing the supernatent liquid to the various solid control units. A pump is connected to the intake conduit and the header at the intake and discharge respectively. The pump transmits the reserve pit supernatent from the reserve pit to the header by pumping. There is provided one or more branch lines affixed to the header each discharging respectively into the drain of a drilling mud treatment unit associated with the drilling rig with the flow of reserve pit supernatent liquid keeping the various drains open. The drains are positioned to discharge back into the reserve pit. The method saves the use of fresh water for the purpose of keeping drains open by the use of the supernatent liquid.
Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs
Maria Cecilia Bravo; Mariano Gurfinkel
2005-06-30T23:59:59.000Z
This document reports progress of this research effort in identifying possible relationships and defining dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight gas sand reservoirs. Based on a critical review of the available literature, a better understanding of the main weaknesses of the current state of the art of modeling and simulation for tight sand reservoirs has been reached. Progress has been made in the development and implementation of a simple reservoir simulator that is still able to overcome some of the deficiencies detected. The simulator will be used to quantify the impact of microscopic phenomena in the macroscopic behavior of tight sand gas reservoirs. Phenomena such as, Knudsen diffusion, electro-kinetic effects, ordinary diffusion mechanisms and water vaporization are being considered as part of this study. To date, the adequate modeling of gas slippage in porous media has been determined to be of great relevance in order to explain unexpected fluid flow behavior in tight sand reservoirs.
Ice Shelves as Floating Channel Flows of Viscous Power-Law Fluids
Banik, Indranil
2013-01-01T23:59:59.000Z
We attempt to better understand the flow of marine ice sheets. Treating ice as a viscous shear-thinning power law fluid, we develop an asymptotic (late-time) theory in two cases - the presence or absence of contact with sidewalls. Most real-world situations fall somewhere between the two extreme cases considered. When sidewalls are absent, we obtain the equilibrium grounding line thickness using a simple computer model and have an analytic approximation. For shelves in contact with sidewalls, we obtain an asymptotic theory, valid for long shelves. Our theory is based on the velocity profile across the channel being a generalised version of Poiseuille flow, which works when lateral shear dominates the force balance. We determine when this is. We conducted experiments using a laboratory model for ice. This was a suspension of xanthan in water, at a concentration of 0.5% by mass. The lab model has $n \\approx 3.8$ (similar to that of ice). The experiments agreed extremely well with our theories for all relevant p...
Global Stability Analysis of Fluid Flows using Sum-of-Squares
2011-07-01T23:59:59.000Z
Jul 1, 2011 ... For finite dimensional approximations of fluid ...... if and only if there exist non-
An investigation of two network flow optimization algorithms
Steelquist, John Anders
1973-01-01T23:59:59.000Z
in Chapter V. The program listing for the Out-of-Kilter algorithm and the SUP ERKIL algorithm can be found in Appendix B and Appendix C. These algorithms are applied to network flow problems. Network flow problems are solved through the application... applications. [ [4 5 12 161 Some of these have clarified and extended the range of applications of the Out-of-Kilter algorithm. Several computer codes have been written to apply the Out-of- Kilter algorithm to actual problems. The code used...
the first order). The dynamic elastic properties of the rock are determined by adding the com- pliance steps, and thus the elastic properties of the rock, for the seismic modeling. The simulation allows us processes--hydraulic frac- turing or induced seismicity--depending on the fluid and rock properties
Doughty, Christine; Takeuchi, Shinji; Amano, Kenji; Shimo, Michito; Tsang, Chin-Fu
2004-10-04T23:59:59.000Z
The flowing fluid electric conductivity (FEC) logging method, wellbore fluid is replaced with de-ionized water, following which FEC profiles in the wellbore are measured at a series of times while the well is pumped at a constant rate. Locations were fluid enters the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow strengths and salinities of permeable features intersected by the wellbore. In multi-rate flowing FEC logging, the flowing FEC logging method is repeated using two or more pumping rates, which enables the transmissivities and inherent pressure heads of these features to be estimated as well. We perform multi-rate FEC logging on a deep borehole in fractured granitic rock, using three different pumping rates. Results identify 19 hydraulically conducting fractures and indicate that transmissivity, pressure head, and salinity vary significantly among them. By using three pumping rates rather than the minimum number of two, we obtain an internal consistency check on the analysis that provides a measure of the uncertainty of the results. Good comparisons against static FEC profiles and against independent chemical, geological, and hydrogeological data have further enhanced confidence in the results of the multi-rate flowing FEC logging method.
Geologic constraints to fluid flow in the Jurassic Arab D reservoir, eastern Saudi Arabia
Laing, J.E. (Saudi Aramco, Dhahran (Saudi Arabia))
1991-08-01T23:59:59.000Z
A giant oil field located in eastern Saudi Arabia has produced several billion barrels of 37{degree} API oil from fewer than 100 wells. The Upper Jurassic Arab Formation is the main producing unit, and is made up of a series of upward-shoaling carbonate and anhydrite members. Porous carbonates of the Arab D member make up the principle oil reservoir, and overlying Arab D anhydrite provides the seal. Principal reservoir facies are stromatoporoid-coral and skeletal grainstones. Reservoir drive is currently provided by flank water injection. Despite more than 30 years of flank water injection (1.5 billion bbl) into the northern area of the field, a thick oil column remains in the Arab D reservoir. Geological factors which affect fluid flow in this area are (1) a downdip facies change from permeable skeletal-stromatoporoid limestone to less permeable micritic limestone, (2) vertical permeability barriers resulting from shoaling-upward cycles, (3) a downdip tar mat, (4) dolomite along the flanks in the upper portion of the reservoir, (5) highly permeable intervals within the skeletal-stromatoporoid limestone, and (6) an updip, north to south facies change from predominantly stromatoporoid-coral grainstone to skeletal grainstone. These factors are considered in reservoir modeling, simulation studies, and planning locations for both water injection and producer wells.
A TWO-STAGE APPROACH TO SOLVING LARGE-SCALE OPTIMAL POWER FLOWS
Gross, George
A TWO-STAGE APPROACH TO SOLVING LARGE-SCALE OPTIMAL POWER FLOWS *F e l i x F. Wu George Gross James problem is formulated as an unconstrained minimization problem using penalty functions and i s solved ] and Sasson and Merrill [ 3 ] . The s i z e and t h e extensive amount of computation involved i n solving t h
Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process
Grujicic, Mica
Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process M Grujicic1*, W, maximizes the acceleration of the particles. Furthermore, it is found that if the cold-spray nozzle, a significant increase in the average velocity of the particles at the nozzle exit can be obtained
The impact of uncertainty on shape optimization of idealized bypass graft models in unsteady flow
Marsden, Alison L.
in the upstream proximal angle. The impact of cost function choice on the optimal solution was explored construction of a graft over a blocked blood vessel. Depending on the location and the underlying disease of surgical geometry on flow fields and hence wall- shear stress WSS , oscillatory shear index OSI , wall
Low, Steven H.
to optimize a certain objective function, such as power loss, generation cost and/or user utilities, subject Power Flow Part II: Exactness Steven H. Low Electrical Engineering, Computing+Mathematical Sciences recent advances in the convex relaxation of the optimal power flow (OPF) problem, focusing on structural
Cornell University Ithaca, NY 14853 Abstract Stability is an important constraint in power system1 A Transient Stability Constrained Optimal Power Flow Deqiang Gan (M) Robert J. Thomas (F) Ray D. The methodology involves a stability constrained Optimal Power Flow (OPF). The theoretical development
Hiroyuki Sato; Richard Johnson; Richard Schultz
2009-09-01T23:59:59.000Z
Three dimensional computational fluid dynamic (CFD) calculations of a typical prismatic very high temperature gas-cooled reactor (VHTR) were conducted to investigate the influence of gap geometry on flow and temperature distributions in the reactor core using commercial CFD code FLUENT. Parametric calculations changing the gap width in a whole core length model of fuel and reflector columns were performed. The simulations show the effects of core by-pass flows in the heated core region by comparing results for several gap widths including zero gap width. The calculation results underline the importance of considering inter-column gap width for the evaluation of maximum fuel temperatures and temperature gradients in fuel blocks. In addition, it is shown that temperatures of core outlet flow from gaps and channels are strongly affected by the gap width of by-pass flow in the reactor core.
Optimality and Conductivity for Water Flow: From Landscapes, to Unsaturated Soils, to Plant Leaves
Liu, H.H.
2012-02-23T23:59:59.000Z
Optimality principles have been widely used in many areas. Based on an optimality principle that any flow field will tend toward a minimum in the energy dissipation rate, this work shows that there exists a unified form of conductivity relationship for three different flow systems: landscapes, unsaturated soils and plant leaves. The conductivity, the ratio of water flux to energy gradient, is a power function of water flux although the power value is system dependent. This relationship indicates that to minimize energy dissipation rate for a whole system, water flow has a small resistance (or a large conductivity) at a location of large water flux. Empirical evidence supports validity of the relationship for landscape and unsaturated soils (under gravity dominated conditions). Numerical simulation results also show that the relationship can capture the key features of hydraulic structure for a plant leaf, although more studies are needed to further confirm its validity. Especially, it is of interest that according to this relationship, hydraulic conductivity for gravity-dominated unsaturated flow, unlike that defined in the classic theories, depends on not only capillary pressure (or saturation), but also the water flux. Use of the optimality principle allows for determining useful results that are applicable to a broad range of areas involving highly non-linear processes and may not be possible to obtain from classic theories describing water flow processes.
Bahrami, Majid
exiting the tube is negligible because of the low velocity (0.36 m/s). 3.139 The horizontal pump in Fig. P264 Solutions Manual x Fluid Mechanics, Fifth Edition Solution: (a) Write the steady flow energy g g ggd D D P D U U U Noting that, in a tube, Q VSd2/4, we may eliminate V in favor of Q
Nikoleris, Teo
1988-01-01T23:59:59.000Z
Fluid in a Rectangular Channel (December 1988) Teo Nikoleris, B. S. , Reed College Chairman of Advisory Committee: Dr. R. Darby An orthogonal collocation finite element program was used to numerically model the hydrodynamicslly and thermally... in negligible increase of Nw~ ~?. Also, the approach of Chang and Finlayson [6], [7] who applied orthogonal collocation finite elements in conjunction with bicubic Hermitian polynomials to approximate various viscoelastic flow problems, also met with little...
Williams, P.T.
1993-09-01T23:59:59.000Z
As the field of computational fluid dynamics (CFD) continues to mature, algorithms are required to exploit the most recent advances in approximation theory, numerical mathematics, computing architectures, and hardware. Meeting this requirement is particularly challenging in incompressible fluid mechanics, where primitive-variable CFD formulations that are robust, while also accurate and efficient in three dimensions, remain an elusive goal. This dissertation asserts that one key to accomplishing this goal is recognition of the dual role assumed by the pressure, i.e., a mechanism for instantaneously enforcing conservation of mass and a force in the mechanical balance law for conservation of momentum. Proving this assertion has motivated the development of a new, primitive-variable, incompressible, CFD algorithm called the Continuity Constraint Method (CCM). The theoretical basis for the CCM consists of a finite-element spatial semi-discretization of a Galerkin weak statement, equal-order interpolation for all state-variables, a 0-implicit time-integration scheme, and a quasi-Newton iterative procedure extended by a Taylor Weak Statement (TWS) formulation for dispersion error control. Original contributions to algorithmic theory include: (a) formulation of the unsteady evolution of the divergence error, (b) investigation of the role of non-smoothness in the discretized continuity-constraint function, (c) development of a uniformly H{sup 1} Galerkin weak statement for the Reynolds-averaged Navier-Stokes pressure Poisson equation, (d) derivation of physically and numerically well-posed boundary conditions, and (e) investigation of sparse data structures and iterative methods for solving the matrix algebra statements generated by the algorithm.
FRACSTIM/I: A Fully Coupled Fluid Flow/Heat Transport and Geomechanica...
Broader source: Energy.gov (indexed) [DOE]
Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power (CSP) Plants Coupled Thermal-Hydrological-Mechanical-Chemical Model And Experiments For...
Bowman, James Albert
1992-01-01T23:59:59.000Z
DISSOLUTION-INDUCED SURFACE MODIFICATIONS AND PERMEABILITY CHANGES ASSOCIATED WITH FLUID FLOW THROUGH AN ABRADED SAW-CUT IN SINGLE CRYSTAL QUARTZ A Thesis by JAlvlES ALBERT BOWMAN, JR, Submined to the Oflice of Graduate Studies of Texas A8r...M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Xiay I992 Major Subject: Geology DISSOLUTION-INDUCED SURFACE MODIFICATIONS AND PERMEABILITY CHANGES ASSOCIATED WITH FLUID FLOW THROUGH AN ABRADED SAW...
Plamin, Sammazo Jean-bertrand
2013-09-29T23:59:59.000Z
Two methods of hydraulic fracturing most widely utilized on unconventional shale gas and oil reservoirs are gelled fracturing and slick-water fracturing. Both methods utilize up to several million gallons of water-based fluid per well in a...
Qureshi, Maha
2013-09-29T23:59:59.000Z
of pertinent chemical additives on fluid imbibition and intercalation into shale samples. We do this with the hope that we will eventually be able to determine how natural phenomena and additives affect long term resource production from unconventional oil...
Plamin, Sammazo Jean-bertrand
2013-09-29T23:59:59.000Z
of pertinent chemical additives on fluid imbibition and intercalation into shale samples. We do this with the hope that we will eventually be able to determine how natural phenomena and additives affect long term resource production from unconventional oil...
is essential in the exploitation of natural fluid resources, such as water, steam, petroleum, and natural gas advantages of our method are the reliability of the testing method, its economy of time, and the flexibility wastes. [3] In general, the nature of fluids in reservoir rocks can be characterized in terms of quantity
Paden, Brad
levitated centrifugal blood pump intended to deliver 0.31.5 l/min of support to neo- nates and infants computational fluid dy- namics (CFD) analysis of impeller refinements, we found that sec- ondary blades located by exten- sive in vitro model testing. Computational fluid dynamics (CFD) has been widely used
Statistical Estimation of Fluid Flow Fields Johnny Chang David Edwards Yizhou Yu
Yu, Yizhou
their motion fields. 1 Introduction Dynamic fluids, such as rivers, ocean waves, moving clouds, smoke and fires (4) where is the kinematic viscosity of the fluid, is its den- sity and f is an external force scale. A good ex- ample is the changing surface geometry of a water surface. This is because the self
Rahatgaonkar, P. S.; Datta, D.; Malhotra, P. K.; Ghadge, S. G. [Nuclear Power Corporation of India Ltd., R-2, Ent. Block, Nabhikiya Urja Bhavan, Anushakti Nagar, Mumbai - 400 094 (India)
2012-07-01T23:59:59.000Z
Prediction of groundwater movement and contaminant transport in soil is an important problem in many branches of science and engineering. This includes groundwater hydrology, environmental engineering, soil science, agricultural engineering and also nuclear engineering. Specifically, in nuclear engineering it is applicable in the design of spent fuel storage pools and waste management sites in the nuclear power plants. Ground water modeling involves the simulation of flow and contaminant transport by groundwater flow. In the context of contaminated soil and groundwater system, numerical simulations are typically used to demonstrate compliance with regulatory standard. A one-dimensional Computational Fluid Dynamics code GFLOW had been developed based on the Finite Difference Method for simulating groundwater flow and contaminant transport through saturated and unsaturated soil. The code is validated with the analytical model and the benchmarking cases available in the literature. (authors)
Swirling structure for mixing two concentric fluid flows at nozzle outlet
Mensink, Daniel L. (3578 Gregory La., Lynchburg, VA 24503)
1993-01-01T23:59:59.000Z
A nozzle device for causing two fluids to mix together. In particular, a spray nozzle comprise two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.
FRACTURING FLUID CHARACTERIZATION FACILITY
Subhash Shah
2000-08-01T23:59:59.000Z
Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.
, and pressure associated with each intra- and extracranial compartment (arteries and arterioles, capillary bed fluid volume] + ["other" volume]) is fixed [7]. Excellent mathematical results and insights, the assumption of fixed brain volume is not ac
Flow through porous media : from mixing of fluids to triggering of earthquakes
Jha, Birendra, Ph. D. Massachusetts Institute of Technology. Department of Civil and Environmental Engineering
2014-01-01T23:59:59.000Z
Enhanced oil recovery by displacing oil with solvents such as carbon dioxide requires development of miscibility between the two fluids to maximize the displacement efficiency. Prevention of inadvertent triggering of ...
Interfacial exchange relations for two-fluid vapor-liquid flow : a simplified regime map approach
Kelly, J. E.
1981-01-01T23:59:59.000Z
A simplified approach is described for selection of the constitutive relations for the inter-phase exchange terms in the two-fluid code, THERMIT. The approach used distinguishes between pre-CHF and post-CHF conditions. ...
Pulsatile flow of a chemically-reacting non-linear fluid
Bridges, Ronald Craig, II
2007-09-17T23:59:59.000Z
Many complex biological systems, such as blood and polymeric materials, can be approximated as single constituent homogeneous fluids whose properties can change because of the chemical reactions that take place. For instance, the viscosity...
Roy, Subrata
by fabrication on the order of micrometers to draw or drain the working fluid in the microfluidic system miniaturization, so that it improves the integration into the microfluidic system. Non-mechanical micropumps
High Flash-point Fluid Flow System Aerosol Flammability Study and Combustion Mechanism Analysis
Huang, Szu-Ying
2013-12-02T23:59:59.000Z
The existence of flammable aerosols creates fire and explosion hazards in the process industry. Due to the operation condition of high pressure circumstances, heat transfer fluids tend to form aerosols when accidental leaking occurs on pipelines...
Price, J.; Indraratna, B. [University of Wollongong, Wollongong, NSW (Australia). School of Civil Engineering
2005-07-01T23:59:59.000Z
Fracture flow of two-phase mixtures is particularly applicable to the coal mining and coal bed methane projects in Australia. A one-dimensional steady-state pseudo-two-phase flow model is proposed for fractured rock. The model considers free flow of a compressible mixture of air and water in an inclined planar fracture and is based upon the conservation of momentum and the 'cubic' law. The flow model is coupled to changes in the stress environment through the fracture normal stiffness, which is related to changes in fracture aperture. The model represents the individual air and water phases as a single equivalent homogenous fluid. Laboratory testing was performed using the two-phase high-pressure triaxial apparatus on 54 mm diameter (approximately 2: 1 height: diameter) borehole cores intersected by induced near-axial fractures. The samples were of Triassic arenaceous fine-medium grained sandstone (known as the Eckersley Formation) that is found locally in the Southern Coalfield of New South Wales. The sample fracture roughness was assessed using a technique based upon Fourier series analysis to objectively attribute a joint roughness coefficient. The proposed two-phase flow model was verified using the recorded laboratory data obtained over a range of triaxial confining pressures (i.e., fracture normal stresses).
The effect of various mixers on the viscosity and flow properties of an oil well drilling fluid
Spannagel, Johnny Allen
1957-01-01T23:59:59.000Z
of Texas in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE January, 1957 MaJor SubJect. Petroleum Englneerlng THE EFFECT OF VARIOUS MIXERS ON THE VISCOSITY AND FLOW PROPERTIES QF AN OIL WELL DRILLING FLUID A Thesis... on the 300 rpm Farm V-G Meter Reading 15 The Effect of Various Mixers on the 600 rpm Farm V-G Meter Reading 15 The Effect of Various Mixers on the Plastic Viscosity of a Bentonite Mud 16 Temperature Variation of the Drilling Mud Mixed in Variou...
Optimization of a high-efficiency jet ejector by computational fluid dynamic software
Watanawanavet, Somsak
2005-08-29T23:59:59.000Z
Computational Fluid Dynamics (CFD) software. A conventional finite-volume scheme was utilized to solve two-dimensional transport equations with the standard k-?? turbulence model (Kim et. al., 1999). In this study of a constant-area jet ejector, all parameters...
Doughty, C.; Pruess, K. [Lawrence Berkeley Lab., CA (United States)
1991-06-01T23:59:59.000Z
Over the past few years the authors have developed a semianalytical solution for transient two-phase water, air, and heat flow in a porous medium surrounding a constant-strength linear heat source, using a similarity variable {eta} = r/{radical}t. Although the similarity transformation approach requires a simplified geometry, all the complex physical mechanisms involved in coupled two-phase fluid and heat flow can be taken into account in a rigorous way, so that the solution may be applied to a variety of problems of current interest. The work was motivated by adverse to predict the thermohydrological response to the proposed geologic repository for heat-generating high-level nuclear wastes at Yucca Mountain, Nevada, in a partially saturated, highly fractured volcanic formation. The paper describes thermal and hydrologic conditions near the heat source; new features of the model; vapor pressure lowering; and the effective-continuum representation of a fractured/porous medium.
Alan Black; Arnis Judzis
2005-09-30T23:59:59.000Z
This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2004 through September 2005. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all Phase 1 testing and is planning Phase 2 development.
Proper initial conditions for the lubrication model of the flow of a thin film of fluid
S. A. Suslov; A. J. Roberts
1998-04-08T23:59:59.000Z
A lubrication model describes the dynamics of a thin layer of fluid spreading over a solid substrate. But to make forecasts we need to supply correct initial conditions to the model. Remarkably, the initial fluid thickness is not the correct initial thickness for the lubrication model. Theory recently developed in \\cite{Roberts89b,Roberts97b} provides the correct projection of initial conditions onto a model of a dynamical system. The correct projection is determined by requiring that the model's solution exponentially quickly approaches that of the actual fluid dynamics. For lubrication we show that although the initial free surface shape contributes the most to the model's initial conditions, the initial velocity field is also an influence. The projection also gives a rationale for incorporating miscellaneous small forcing effects into the lubrication model; gravitational forcing is given as one example.
Numerical studies on two-way coupled fluid flow and geomechanics in hydrate deposits
Kim, J.
2014-01-01T23:59:59.000Z
A. 2008. Modeling of Geomechanics in Naturally Fracturedcoupling porous flow and geomechanics. Soc. Pet. Eng. J. 11(a reservoir simulator and a geomechanics module. Soc. Pet.
Use of Geophysical Techniques to Characterize Fluid Flow in a Geothermal Reservoir
Broader source: Energy.gov [DOE]
Project objectives: Joint inversion of geophysical data for ground water flow imaging; Reduced the cost in geothermal exploration and monitoring; & Combined passive and active geophysical methods.
A Site-Scale Model For Fluid And Heat Flow In The Unsaturated...
heat at Yucca Mountain, Nevada, a potential repository site for high-level radioactive waste. The model takes into account the simultaneous flow dynamics of liquid water, vapor,...
Marques, Alexandre Noll
2012-01-01T23:59:59.000Z
Numerical simulations of incompressible viscous flows in realistic configurations are increasingly important in many scientific and engineering fields. In Aeronautics, for instance, relatively cheap numerical computations ...
Xu , Huan
A Simple Optimal Power Flow Model with Energy Storage K. Mani Chandy, Steven H. Low, Ufuk Topcu and Huan Xu Abstract-- The integration of renewable energy generation, such as wind power how storage allows optimization of power generation across multiple time periods. The model
IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 15, NO. 2, MAY 2000 535 Stability-Constrained Optimal Abstract--Stability is an important constraint in power system operation. Often trial and error heuristics in the context of a 162-bus system. Index Terms--Power System, Transient Stability, Optimal Power Flow, Numerical
NMR imaging techniques and applications in the flow behavior of fluids in porous media
Halimi, Hassan I
1990-01-01T23:59:59.000Z
proton magnetic resonance technique can be used to determine the oil saturation in the pores of a rock. The NMR system can produce images of the molecules under investigation because the signals recorded are obtained directly from fluids contained... in liquids as well. This should enable us to obtain additional information about the fluids in the rock '4. Spin-spin relaxation has a characteristic time T~. T~ is the time constant for the decay of the precessing R-Zo component of the magnetization...
Rutqvist, J.
2010-06-01T23:59:59.000Z
This paper presents recent advancement in and applications of TOUGH-FLAC, a simulator for multiphase fluid flow and geomechanics. The TOUGH-FLAC simulator links the TOUGH family multiphase fluid and heat transport codes with the commercial FLAC{sup 3D} geomechanical simulator. The most significant new TOUGH-FLAC development in the past few years is a revised architecture, enabling a more rigorous and tight coupling procedure with improved computational efficiency. The applications presented in this paper are related to modeling of crustal deformations caused by deep underground fluid movements and pressure changes as a result of both industrial activities (the In Salah CO{sub 2} Storage Project and the Geysers Geothermal Field) and natural events (the 1960s Matsushiro Earthquake Swarm). Finally, the paper provides some perspectives on the future of TOUGH-FLAC in light of its applicability to practical problems and the need for high-performance computing capabilities for field-scale problems, such as industrial-scale CO{sub 2} storage and enhanced geothermal systems. It is concluded that despite some limitations to fully adapting a commercial code such as FLAC{sup 3D} for some specialized research and computational needs, TOUGH-FLAC is likely to remain a pragmatic simulation approach, with an increasing number of users in both academia and industry.
Grothey, Andreas
is primarily due to Kirchhoff's voltage law (KVL), which describes the flow of power in transmission lines that minimizes the cost of electric power generation while satisfying operating constraints and meeting demandLocal Solutions of Optimal Power Flow Waqquas A. Bukhsh, Andreas Grothey, Ken McKinnon, and Paul
LETTER TO THE EDITOR AC Electric-Field-Induced Fluid Flow in Microelectrodes
glass substrates. The electrodes were made from a series of metal layers: 10 nm Ti, 10 nm Pd, 100 nm Au relaxation time, with a reproducible pattern occurring close to and across the electrode surface. This paper reports measurements of the fluid velocity as a function of frequency and position across the electrode
A Well-Balanced Scheme For Two-Fluid Flows In Variable Cross-Section ducts
Paris-Sud XI, Université de
, ) p = p(, s, ), h = h(, s, ). (21) Then in these variables the sound speed c satisfies c2 = p = h. (22 of a mixture of two compressible fluids (a gas (1) and a liquid (2), for instance) in a cross-section duct
Large-scale optimal power flow: Effects of initialization, decoupling and discretization
Papalexopoulos, A.D.; Imparato, C.F.; Wu, F.F.
1989-08-01T23:59:59.000Z
The optimal power flow has entered a new era since the introduction of second-order methods. These methods have renewed hopes for its on-line application in Energy Management Systems. This paper reports on some of the results of tests of a second-order OPF method. The testing was conducted using a 1500 bus network, under a variety of loading conditions. Three issues were studied: Sensitivity of OPF solutions with respect to the starting points used in the solution; Accuracy of the active/reactive decoupled approach to OPF solution; Effects of discretization of transformer taps on the OPF solutions.
Online Optimal Control of Connected Vehicles for Efficient Traffic Flow at Merging Roads
Rios-Torres, Jackeline [ORNL; Malikopoulos, Andreas [ORNL; Pisu, Pierluigi [Clemson University
2015-01-01T23:59:59.000Z
This paper addresses the problem of coordinating online connected vehicles at merging roads to achieve a smooth traffic flow without stop-and-go driving. We present a framework and a closed-form solution that optimize the acceleration profile of each vehicle in terms of fuel economy while avoiding collision with other vehicles at the merging zone. The proposed solution is validated through simulation and it is shown that coordination of connected vehicles can reduce significantly fuel consumption and travel time at merging roads.
Study of Laminar Flow Forced Convection Heat Transfer Behavior of a Phase Change Material Fluid
Ravi, Gurunarayana
2010-01-14T23:59:59.000Z
with constant peripheral temperature and uniform axial and peripheral temperature, were considered in the case of circular tubes. An effective specific heat technique was used to model the phase change process assuming a hydrodynamically fully-developed flow...
Abdou, Mohamed
2007-01-01T23:59:59.000Z
flow path design for an ITER solid breeder blanket module A. Yinga,, M. Narulaa, R. Hunta, M. Abdoua, Y breeder blanket design. Supplying all s the ITER test blanket module (TBM) warrants the need of extensive computer aided engineering (CAE
Fluid Flow In The Resurgent Dome Of Long Valley Caldera- Implications...
caldera was cooled to normal thermal conditions by vigorous hydrothermal activity in the past, and that a present-day hot water flow system is responsible for local hot anomalies,...
Alfred, Dicman
2004-09-30T23:59:59.000Z
This research presents an approach to accurately simulate flow experiments through a fractured core using experimental, stochastic, and simulation techniques. Very often, a fracture is assumed as a set of smooth parallel plates separated by a...
Review of fluid flow and convective heat transfer within rotating disk cavities
Boyer, Edmond
-00975626,version1-8Apr2014 Author manuscript, published in "International Journal of Thermal Sciences 67 based on and r. Rej Jet Reynolds number based on W and D. ReU Cross-flow Reynolds number Ro Rossby
On the Fundamental Unsteady Fluid Dynamics of Shock-Induced Flows through Ducts
Mendoza, Nicole Renee
2013-04-29T23:59:59.000Z
Unsteady shock wave propagation through ducts has many applications, ranging from blast wave shelter design to advanced high-speed propulsion systems. The research objective of this study was improved fundamental understanding of the transient flow...
Electromechanics and electrorheology of fluid flow with internal micro-particle electrorotation
Huang, Hsin-Fu
2010-01-01T23:59:59.000Z
The negative electrorheological responses of two dimensional Couette and Poiseuille flows with internal micro-particle electrorotation are modeled and analyzed via a set of "fully continuum mechanical modeling field ...
Unified formal reduction for fluid models of free-surface shallow gravity-flows
Paris-Sud XI, Universit de
modelling of the rheology in e.g. mud flows and land- slides, which are still much investigated model provided the assumptions used for the derivation hold. We obtain a synthetic viewpoint of various
PROBABILISTIC SIMULATION OF SUBSURFACE FLUID FLOW: A STUDY USING A NUMERICAL SCHEME
Buscheck, Timothy Eric
1980-03-01T23:59:59.000Z
There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeologic parameter, given a particular scale of interest. However, physically there is no such entity as a truly uniform and homogeneous unit. Single-number representations or deterministic predictions are subject to uncertainties. The approach used in this work models such uncertainties with probabilistic parameters. The resulting statistical distributions of output variables are analyzed. A numerical algorithm, based on axiomatic principles of probability theory, performs arithmetic operations between probability distributions. Two subroutines are developed from the algorithm and incorporated into the computer program TERZAGI, which solves groundwater flow problems in saturated, multi-dimensional systems. The probabilistic computer program is given the name, PROGRES. The algorithm has been applied to study the following problems: one-dimensional flow through homogeneous media, steady-state and transient flow conditions, one-dimensional flow through heterogeneous media, steady-state and transient flow conditions, and two-dimensional steady-stte flow through heterogeneous media. The results are compared with those available in the literature.
Impact of relative permeability models on fluid flow behavior for gas condensate reservoirs
Zapata Arango, Jose? Francisco
2002-01-01T23:59:59.000Z
. 6 Integral from immiscible to miscible transition models for gas condensate relative permeability. 5 . 6 . . 8 9 . 10 . 12 . 16 . 18 . 20 . 23 CHAPTER III CASE STUDY. . . 27 3. 1 Tuning of the reservoir fluid model 3. 2 Relative... model . 5. 2. 2 Anisotropic model . 64 . 74 . 77 . 90 CHAPTER VI SUMMARY . 105 6. 1 Conclusions. . 6. 1. 1 Conclusions from the literature review and case study . . . . . . 6. 1. 2 Conclusions from the simulation study 6. 1. 3 Conclusions from...
Impact of relative permeability models on fluid flow behavior for gas condensate reservoirs
Zapata Arango, Jose? Francisco
2002-01-01T23:59:59.000Z
. 6 Integral from immiscible to miscible transition models for gas condensate relative permeability. 5 . 6 . . 8 9 . 10 . 12 . 16 . 18 . 20 . 23 CHAPTER III CASE STUDY. . . 27 3. 1 Tuning of the reservoir fluid model 3. 2 Relative... model . 5. 2. 2 Anisotropic model . 64 . 74 . 77 . 90 CHAPTER VI SUMMARY . 105 6. 1 Conclusions. . 6. 1. 1 Conclusions from the literature review and case study . . . . . . 6. 1. 2 Conclusions from the simulation study 6. 1. 3 Conclusions from...
Davis, Michael A.
2011-10-21T23:59:59.000Z
the static pressure drop as air passed through the unit over the full operating range of the FPTU. Computational fluid dynamics (CFD) models of typical a FPTU were developed and used to investigate opportunities for optimizing the design of FPTUs. The CFD...
Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.; Perkins, William A.
2010-12-01T23:59:59.000Z
In 2003, an extension of the existing ice and trash sluiceway was added at Bonneville Powerhouse 2 (B2). This extension started at the existing corner collector for the ice and trash sluiceway adjacent to Bonneville Powerhouse 2 and the new sluiceway was extended to the downstream end of Cascade Island. The sluiceway was designed to improve juvenile salmon survival by bypassing turbine passage at B2, and placing these smolt in downstream flowing water minimizing their exposure to fish and avian predators. In this study, a previously developed computational fluid dynamics model was modified and used to characterized tailrace hydraulics and sluiceway egress conditions for low total river flows and low levels of spillway flow. STAR-CD v4.10 was used for seven scenarios of low total river flow and low spill discharges. The simulation results were specifically examined to look at tailrace hydraulics at 5 ft below the tailwater elevation, and streamlines used to compare streamline pathways for streamlines originating in the corner collector outfall and adjacent to the outfall. These streamlines indicated that for all higher spill percentage cases (25% and greater) that streamlines from the corner collector did not approach the shoreline at the downstream end of Bradford Island. For the cases with much larger spill percentages, the streamlines from the corner collector were mid-channel or closer to the Washington shore as they moved downstream. Although at 25% spill at 75 kcfs total river, the total spill volume was sufficient to "cushion" the flow from the corner collector from the Bradford Island shore, areas of recirculation were modeled in the spillway tailrace. However, at the lowest flows and spill percentages, the streamlines from the B2 corner collector pass very close to the Bradford Island shore. In addition, the very flow velocity flows and large areas of recirculation greatly increase potential predator exposure of the spillway passed smolt. If there is concern for egress issues for smolt passing through the spillway, the spill pattern and volume need to be revisited.
Sundar, Sita; Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)
2012-05-15T23:59:59.000Z
In the interaction of intense lasers with matter/plasma, energetic electrons having relativistic energies get created. These energetic electrons can often have sheared flow profiles as they propagate through the plasma medium. In an earlier study [Phys. Plasmas 17, 022101 (2010)], it was shown that a relativistic sheared electron flow modifies the growth rate and threshold condition of the conventional Kelvin-Helmholtz instability. A perturbative analytic treatment for the case of weakly relativistic regime has been provided here. It provides good agreement with the numerical results obtained earlier.
On the terminal velocity of sedimenting particles in a flowing fluid
Marco Martins Afonso
2008-06-11T23:59:59.000Z
The influence of an underlying carrier flow on the terminal velocity of sedimenting particles is investigated both analytically and numerically. Our theoretical framework works for a general class of (laminar or turbulent) velocity fields and, by means of an ordinary perturbation expansion at small Stokes number, leads to closed partial differential equations (PDE) whose solutions contain all relevant information on the sedimentation process. The set of PDE's are solved by means of direct numerical simulations for a class of 2D cellular flows (static and time dependent) and the resulting phenomenology is analysed and discussed.
Barton, C.C.; Larsen, E.; Page, W.R.; Howard, T.M.
1993-12-31T23:59:59.000Z
Fractures have been characterized for fluid-flow, geomechanical, and paleostress modeling at three localities in the vicinity of drill hole USW G-4 at Yucca Mountain in southwestern Nevada. A method for fracture characterization is introduced that integrates mapping fracture-trace networks and quantifying eight fracture parameters: trace length, orientation, connectivity, aperture, roughness, shear offset, trace-length density, and mineralization. A complex network of fractures was exposed on three 214- to 260-m 2 pavements cleared of debris in the upper lithophysal unit of the Tiva Canyon Member of the Miocene Paint-brush Tuff. The pavements are two-dimensional sections through the three-dimensional network of strata-bound fractures. All fractures with trace lengths greater than 0.2 m were mapped and studied.
Viscoelastic fluid flow in a 2D channel bounded above by a deformable finite thickness elastic wall
Chakraborty, Debadi
2015-01-01T23:59:59.000Z
The steady flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens model for blood) in a two-dimensional channel, partly bound by a deformable, finite thickness neo-Hookean solid, is computed. The limiting Weissenberg number beyond which computations fail to converge is found to increase with increasing dimensionless solid elasticity parameter {\\Gamma}, following the trend Owens > FENE- P > Oldroyd-B. The highly shear thinning nature of Owens model leads to the elastic solid always collapsing into the channel, for the wide range of values of {\\Gamma} considered here. In the case of the FENE-P and Oldroyd-B models, however, the fluid-solid interface can be either within the channel, or bulge outwards, depending on the value of {\\Gamma}. This behaviour differs considerably from predictions of earlier models that treat the deformable solid as a zero-thickness membrane, in which case the membrane always lies within the channel. The capacity of the solid wall to support both pressure and shear stress, in c...
Christian Kreuzer; Endre Sli
2015-03-18T23:59:59.000Z
We develop the a posteriori error analysis of finite element approximations of implicit power-law-like models for viscous incompressible fluids. The Cauchy stress and the symmetric part of the velocity gradient in the class of models under consideration are related by a, possibly multi--valued, maximal monotone $r$-graph, with $\\frac{2d}{d+1}finite element residual, as well as the local stability of the error bound. We then consider an adaptive finite element approximation of the problem, and, under suitable assumptions, we show the weak convergence of the adaptive algorithm to a weak solution of the boundary-value problem. The argument is based on a variety of weak compactness techniques, including Chacon's biting lemma and a finite element counterpart of the Acerbi--Fusco Lipschitz truncation of Sobolev functions, introduced by L. Diening, C. Kreuzer and E. S\\"uli [Finite element approximation of steady flows of incompressible fluids with implicit power-law-like rheology. SIAM J. Numer. Anal., 51(2), 984--1015].
Mukhopadhyay, Sumit; Tsang, Yvonne W.
2008-08-01T23:59:59.000Z
Flowing fluid temperature logging (FFTL) has been recently proposed as a method to locate flowing fractures. We argue that FFTL, backed up by data from high-precision distributed temperature sensors, can be a useful tool in locating flowing fractures and in estimating the transport properties of unsaturated fractured rocks. We have developed the theoretical background needed to analyze data from FFTL. In this paper, we present a simplified conceptualization of FFTL in unsaturated fractured rock, and develop a semianalytical solution for spatial and temporal variations of pressure and temperature inside a borehole in response to an applied perturbation (pumping of air from the borehole). We compare the semi-analytical solution with predictions from the TOUGH2 numerical simulator. Based on the semi-analytical solution, we propose a method to estimate the permeability of the fracture continuum surrounding the borehole. Using this proposed method, we estimated the effective fracture continuum permeability of the unsaturated rock hosting the Drift Scale Test (DST) at Yucca Mountain, Nevada. Our estimate compares well with previous independent estimates for fracture permeability of the DST host rock. The conceptual model of FFTL presented in this paper is based on the assumptions of single-phase flow, convection-only heat transfer, and negligible change in system state of the rock formation. In a sequel paper [Mukhopadhyay et al., 2008], we extend the conceptual model to evaluate some of these assumptions. We also perform inverse modeling of FFTL data to estimate, in addition to permeability, other transport parameters (such as porosity and thermal conductivity) of unsaturated fractured rocks.
Numerical simulation of flow of shear-thinning fluids in corrugated channels
Aiyalur Shankaran, Rohit
2009-05-15T23:59:59.000Z
is subjected to a periodic increase and decrease in cross-section area. Such conditions are frequently observed in the flow of blood through blood vessels, movement of lubricating oils through the ground during the oil extraction process, in the process...
Numerical simulation of flow of shear-thinning fluids in corrugated channels
Aiyalur Shankaran, Rohit
2008-10-10T23:59:59.000Z
is subjected to a periodic increase and decrease in cross-section area. Such conditions are frequently observed in the flow of blood through blood vessels, movement of lubricating oils through the ground during the oil extraction process, in the process...
Multiphase flow and Encapsulation simulations using the moment of fluid method 1
Sussman, Mark
in order to demonstrate its capabilities. Examples are given in 2D, 3D axisymmetric (R-Z), and 3D (X Corporation, for the U. S. Department of Energy's National Nuclear Security Administration under contract DE. Introduction Multiphase flow plays an important role in many technical applications including ink-jet printing
Slip Flow Fluid-Structure-Interaction J. van Rij, T. Harman, T. Ameel*
Utah, University of
per unit mass E Young's modulus of elasticity, ( )KGGK 39 + f force per unit volume FD drag force Fo Fourier number, 2 Dt G shear modulus of elasticity * Corresponding author. Tel.: +1-801-585-9730; fax: +1 moment of inertia K bulk modulus of elasticity rsK momentum exchange coefficient slip rsK slip flow
Zakaria Mohamed Reda, Ahmed
2014-07-29T23:59:59.000Z
the flow behavior in vuggy rocks, including the more pronounced works of Hidajat et al. (2004), Moctezuma Berthier et al. (2000), Xu et al. (1998), Zhang et al. (2004 and 2005), and Arbogast et al. (2004). Zhang et al. (2005) conducted number...
Under consideration for publication in J. Fluid Mech. 1 Hydrodynamic effects in channel flow due to
Sen, Mihir
is that of a boundary layer exposed to wall vi- brations. The concept of complia the resulting linear system of equations. Resonance is found in the oscillatory flow at a Strohaul num- ber be applied. 1. Introduction Unsteady boundaries commonly occur in many engineering as well as natural applica
Two-fluid flowing equilibria of compact plasmas Loren C. Steinhauer
Washington at Seattle, University of
or presence of a j?B force. The force-free class may have significant flows. Spheromaks are in this class-force-free class is energetically favorable. This sheds light on the FRC-spheromak bifurcation observed- perimentally only in certain arrangements reversed-field pinch, spheromak and then only in the central ``core
Physics-Based Low Order Galerkin Models in Fluid Dynamics & Flow Control
Gorban, Alexander N.
(Berlin Institute of Technology MB1, Germany) Marek Morzynski (Poznan University of Technology, Poland models of energy supply and consumption. Yet a third principle is the realization that governing flow to time-averaged energy dynamics of Galerkin modes, and gives rise to physically based, nonlinear sub
Imaging Fluid Flow in Geothermal Wells Using Distributed Thermal Perturbation Sensing
Broader source: Energy.gov [DOE]
Project objective: A New Geothermal Well Imaging Tool. 1.To develop a robust and easily deployable DTPS for monitoring in geothermal wells; and 2. Develop the associated analysis methodology for flow imaging; and?when possible by wellbore conditions?to determine in situthermal conductivity and basal heat flux.
Adolphs, Ralph
, 2002. 1. Introduction [2] Detecting subsurface groundwater circulation using geophysical methods to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes. Numerical modeling indicates that the spatial
Paris-Sud XI, Université de
spaced, vertical glass plates. Such a "rivulet" is bounded by two liquid/solid and two mobile liquid/gas interfaces, posing fluid dynamic problems of direct relevance to local fluid flow in liquid foams/liquid or liquid/gas interfaces, as found in foams and emulsions, which respond to flow by adjusting their shape
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
The Center for Computational Sciences and Engineering (CCSE) develops and applies advanced computational methodologies to solve large-scale scientific and engineering problems arising in the Department of Energy (DOE) mission areas involving energy, environmental, and industrial technology. The primary focus is in the application of structured-grid finite difference methods on adaptive grid hierarchies for compressible, incompressible, and low Mach number flows. The diverse range of scientific applications that drive the research typically involve a large range of spatial and temporal scales (e.g. turbulent reacting flows) and require the use of extremely large computing hardware, such as the 153,000-core computer, Hopper, at NERSC. The CCSE approach to these problems centers on the development and application of advanced algorithms that exploit known separations in scale; for many of the application areas this results in algorithms are several orders of magnitude more efficient than traditional simulation approaches.
Proceedings: Joint DOE/NSF Workshop on flow of particulates and fluids
Not Available
1993-12-31T23:59:59.000Z
These proceedings are the result of the Fifth DOR-NSF Workshop on fundamental research in the area of particulate two-phase flow and granular flow. The present collection of twenty contributions from universities and national laboratories is based on research projects sponsored by either the Department of Energy or the National Science Foundation. These papers illustrate some of the latest advances in theory, simulations, and experiments. The papers from the Workshop held September 29--October 1, 1993 have been separated into three basic areas: experiments, theory, and numerical simulations. A list of attendees at the workshop is included at the end of the proceedings. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.
Identification of fluid-flow paths in the Cerro Prieto geothermal field
Halfman, S.E.; Lippmann, M.J.; Zelwer, R.; Howard, J.H.
1982-05-01T23:59:59.000Z
A hydrogeologic model of the Cerro Prieto geothermal field has been developed based on geophysical and lithologic well logs, downhole temperature, and well completion data from about 90 deep wells. The hot brines seem to originate in the eastern part of the field, flowing in a westward direction and rising through gaps in the shaly layers which otherwise act as partial caprocks to the geothermal resource.
Grujicic, Mica
2005-01-01T23:59:59.000Z
Materials Science and Engineering B 117 (2005) 5361 Finite element analysis-based design A finite element method-based procedure is developed for the design of molecularly functionalized nano of a fluid-flow control nano-valve. The results obtained suggest that the finite element-based procedure
McHugh, P.R.; Ramshaw, J.D.
1991-11-01T23:59:59.000Z
MAGMA is a FORTRAN computer code designed to viscous flow in in situ vitrification melt pools. It models three-dimensional, incompressible, viscous flow and heat transfer. The momentum equation is coupled to the temperature field through the buoyancy force terms arising from the Boussinesq approximation. All fluid properties, except density, are assumed variable. Density is assumed constant except in the buoyancy force terms in the momentum equation. A simple melting model based on the enthalpy method allows the study of the melt front progression and latent heat effects. An indirect addressing scheme used in the numerical solution of the momentum equation voids unnecessary calculations in cells devoid of liquid. Two-dimensional calculations can be performed using either rectangular or cylindrical coordinates, while three-dimensional calculations use rectangular coordinates. All derivatives are approximated by finite differences. The incompressible Navier-Stokes equations are solved using a new fully implicit iterative technique, while the energy equation is differenced explicitly in time. Spatial derivatives are written in conservative form using a uniform, rectangular, staggered mesh based on the marker and cell placement of variables. Convective terms are differenced using a weighted average of centered and donor cell differencing to ensure numerical stability. Complete descriptions of MAGMA governing equations, numerics, code structure, and code verification are provided. 14 refs.
Fakcharoenphol, Perapon [Colorado School of Mines; Xiong, Yi [Colorado School of Mines; Hu, Litang; Winterfeld, Philip H. [Colorado School of Mines; Xu, Tianfu [Lawrence Berkeley National Laboratory; Wu, Yu-Shu [Colorado School of Mines
2013-05-01T23:59:59.000Z
TOUGH2-EGS is a numerical simulation program coupling geomechanics and chemical reactions for fluid and heat flows in porous media and fractured reservoirs of enhanced geothermal systems. The simulator includes the fully-coupled geomechanical (THM) module, the fully-coupled geochemical (THC) module, and the sequentially coupled reactive geochemistry (THMC) module. The fully-coupled flow-geomechanics model is developed from the linear elastic theory for the thermo-poro-elastic system and is formulated with the mean normal stress as well as pore pressure and temperature. The chemical reaction is sequentially coupled after solution of flow equations, which provides the flow velocity and phase saturation for the solute transport calculation at each time step. In addition, reservoir rock properties, such as porosity and permeability, are subjected to change due to rock deformation and chemical reactions. The relationships between rock properties and geomechanical and chemical effects from poro-elasticity theories and empirical correlations are incorporated into the simulator. This report provides the user with detailed information on both mathematical models and instructions for using TOUGH2-EGS for THM, THC or THMC simulations. The mathematical models include the fluid and heat flow equations, geomechanical equation, reactive geochemistry equations, and discretization methods. Although TOUGH2-EGS has the capability for simulating fluid and heat flows coupled with both geomechanical and chemical effects, it is up to the users to select the specific coupling process, such as THM, THC, or THMC in a simulation. There are several example problems illustrating the applications of this program. These example problems are described in details and their input data are presented. The results demonstrate that this program can be used for field-scale geothermal reservoir simulation with fluid and heat flow, geomechanical effect, and chemical reaction in porous and fractured media.
Elliptic flow fluctuations in heavy ion collisions at RHIC and the perfect fluid hypothesis
Sascha Vogel; Giorgio Torrieri; Marcus Bleicher
2010-08-05T23:59:59.000Z
We analyse the recently measured $v_2$ fluctuation in the context of establishing the degree of fluidity of the matter produced in heavy ion collisions. We argue that flow observables within systems with a non-negligible mean free path should acquire a "dynamical" fluctuation, due to the random nature of each collision between the system's degrees of freedom. Because of this, $v_2$ fluctuations can be used to estimate the Knudsen number of the system produced at RHIC. To illustrate this quantitatively, we apply the UrQMD model, with scaled cross sections, to show that collisions at RHIC have a Knudsen number at least one order of magnitude above the expected value for an interacting hadron gas. Furthermore, we argue that the Knudsen number is also bound from above by the $v_2$ fluctuation data, because too large a Knudsen number would break the observed scaling of $v_2$ fluctuations due to the onset of turbulent flow. We propose, therefore that $v_2$ fluctuation measurements, together with an understanding of the turbulent regime for relativistic hydrodynamics, will provide an upper as well as a lower limit for the Knudsen number.
Development of an entrained flow gasifier model for process optimization study
Biagini, E.; Bardi, A.; Pannocchia, G.; Tognotti, L. [Consorzio Pisa Ric, Pisa (Italy). Div Energia Ambiente
2009-10-15T23:59:59.000Z
Coal gasification is a versatile process to convert a solid fuel in syngas, which can be further converted and separated in hydrogen, which is a valuable and environmentally acceptable energy carrier. Different technologies (fixed beds, fluidized beds, entrained flow reactors) are used, operating under different conditions of temperature, pressure, and residence time. Process studies should be performed for defining the best plant configurations and operating conditions. Although 'gasification models' can be found in the literature simulating equilibrium reactors, a more detailed approach is required for process analysis and optimization procedures. In this work, a gasifier model is developed by using AspenPlus as a tool to be implemented in a comprehensive process model for the production of hydrogen via coal gasification. It is developed as a multizonal model by interconnecting each step of gasification (preheating, devolatilization, combustion, gasification, quench) according to the reactor configuration, that is in entrained flow reactor. The model removes the hypothesis of equilibrium by introducing the kinetics of all steps and solves the heat balance by relating the gasification temperature to the operating conditions. The model allows to predict the syngas composition as well as quantity the heat recovery (for calculating the plant efficiency), 'byproducts', and residual char. Finally, in view of future works, the development of a 'gasifier model' instead of a 'gasification model' will allow different reactor configurations to be compared.
A numerical study of steady fluid flow in the entry region of a straight circular tube
Crain, John Kee
1967-01-01T23:59:59.000Z
region. The Basic Equations The flow under i nves ti gati on is governed by the Navier-Stokes equations p ? = F - . + uv Du Dt x ax p ? = F - @uv v, Dv a A 2 Dt y ay (2) Dw= F ma+ Dt w as and the continuity equation "u av aw + ? = p ay... + w D a a a a Ut = at ax ay as and 2 a2 a2 a2 ax2 ay2 as2 Expressed in cylindrical form, the previous equations become 2 P = Fr M + & v V r e D Ve 2aV Dt r " ar r2ae DVe V Ve 2aV V p + ? = Fe - ~a + u & Ve + r - e Dt r rae (2a) F -22+ pv V...
power plants, nuclear power plants etc and selling power to consumers. The suppliers have contractsOptimal Power Flow Formulation in Market of Retail Wheeling Taiyou Yong, Student Member, IEEE at Madison, Madison, Wisconsin, USA Abstract: Power system deregulation along with retail wheeling
algorithms to handle this problem for the e - 1 security constrained optimal power flow problem. We also.3. The MATPOWER package 4 2.4. Graph theoretic notions 4 3. Security constrained optimal power flow 5 3, such as the breakdown of a generator or a fault in some transmission line. The importance of being able to supply power
S Maiti; J. C. Misra
2011-07-28T23:59:59.000Z
The paper deals with a theoretical study of the transport of a fluid in a channel, which takes place by the phenomenon of peristalsis. A mathematical analysis of the said problem has been presented. The analysis involves the application of a suitable perturbation technique. The velocity profile and the critical pressure for the occurrence of reflux are investigated with particular emphasis by using appropriate numerical methods. The effects of various parameters, such as Reynolds number, pressure gradient, porosity parameter, Darcy number, slip parameter, amplitude ratio and wave number on velocity and critical pressure for reflux are investigated in detail. The computed results are compared with a previous analytical work and an experimental investigation reported earlier in existing scientific literatures. The results of the present study are in conformity to both of them. The study has got some relevance to the physiological flow of bile in the common bile duct in a pathological state. It reveals that in the presence of gallstones, bile velocity increases as the value of the porosity parameter increases, while the critical pressure for reflux decreases as porosity increases.
Soto, Enrique
2013-01-01T23:59:59.000Z
This fluid dynamics video is an entry for the Gallery of Fluid Motion for the 66th Annual Meeting of the Fluid Dynamics Division of the American Physical Society. We show the curious behaviour of a light ball interacting with a liquid jet. For certain conditions, a ball can be suspended into a slightly inclined liquid jet. We studied this phenomenon using a high speed camera. The visualizations show that the object can be `juggled' for a variety of flow conditions. A simple calculation showed that the ball remains at a stable position due to a Bernoulli-like effect. The phenomenon is very stable and easy to reproduce.
CSE Master Specialization Fluid Dynamics
Lang, Annika
CSE Master Specialization Fluid Dynamics Course Semester Fluid Dynamics II HS Quantitative Flow Energie- und Verfahrenstechnik FS Biofluiddynamics FS #12;CSE in Fluid Dynamics: Very large high in Fluid Dynamics: Physiology of the inner ear MicroCT imaging Multilayer MFS for Stokes flow simulations
Donahoe, R.J.
1986-09-01T23:59:59.000Z
A low-temperature hydrothermal flow-through study was conducted experimentally examine fluid/rock interactions brought about in sandstones as a result of fluid injection enhanced oil recovery (EOR) methods. Such studies will eventually enable the development of a predictive model for fluid injection EOR methods. The design of the low-temperature hydrothermal flow-through system allows the accurate control of fluid flow rate (0.002-10 ml/min), temperature (0 to 300/sup 0/C) and pressure (1 to 500 bar) while flowing fluids through disaggregated solid samples. Samples of St. Peter Sandstone and two different sandstones of the Norphlet Formation from southern Alabama were interacted with distilled, deionized water and a 1% HC1 solution at 250/sup 0/C, 300 bar and 0.1 or 0.5 ml/min fluid flow rate. Solids were analyzed by x-ray powder diffraction and scanning electron microscopy. Fluid samples were analyzed by atomic absorption spectrophotometry and combination pH electrode. A variety of processes which occur in sandstones subjected to fluid injection EOR methods were documented experimentally. Processes damaging to reservoir permeability included iron fouling, silica fouling, migration of clay fines, and precipitation of other secondary phases. Processes resulting in reservoir stimulation involved the dissolution of sandstone framework and/or authigenic mineral constituents. The most successful fluid injection stimulation can be expected for arkosic sandstones containing high percentages of K-feldspar and illite relative to kaolinite, chlorite and smectite, using dilute HCl injection solutions and high fluid flow rates. Fluid chemical data indicate that equilibrium between the solid and injection fluid is not approached for any of the experiments. Therefore, it does not appear that chemical equilibrium computer programs can be used to model these low-temperature reactions. 12 refs., 11 figs., 4 tabs.
Alan Black; Arnis Judzis
2003-10-01T23:59:59.000Z
This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2002 through September 2002. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit--fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. Accomplishments to date include the following: 4Q 2002--Project started; Industry Team was assembled; Kick-off meeting was held at DOE Morgantown; 1Q 2003--Engineering meeting was held at Hughes Christensen, The Woodlands Texas to prepare preliminary plans for development and testing and review equipment needs; Operators started sending information regarding their needs for deep drilling challenges and priorities for large-scale testing experimental matrix; Aramco joined the Industry Team as DEA 148 objectives paralleled the DOE project; 2Q 2003--Engineering and planning for high pressure drilling at TerraTek commenced; 3Q 2003--Continuation of engineering and design work for high pressure drilling at TerraTek; Baker Hughes INTEQ drilling Fluids and Hughes Christensen commence planning for Phase 1 testing--recommendations for bits and fluids.
Abgrall, Rmi, E-mail: remi.abgrall@inria.fr [Bacchus Team Project, Domaine de Voluceau Rocquencourt - B.P. 105 78153 Le Chesnay (France) [Bacchus Team Project, Domaine de Voluceau Rocquencourt - B.P. 105 78153 Le Chesnay (France); Institut de Mathmatiques de Bordeaux, Universit de Bordeaux, 351 Cours de la Libration, 33405 Talence (France); Congedo, Pietro Marco [Bacchus Team Project, Domaine de Voluceau Rocquencourt - B.P. 105 78153 Le Chesnay (France) [Bacchus Team Project, Domaine de Voluceau Rocquencourt - B.P. 105 78153 Le Chesnay (France); Institut de Mathmatiques de Bordeaux, Universit de Bordeaux, 351 Cours de la Libration, 33405 Talence (France)
2013-02-15T23:59:59.000Z
This paper deals with the formulation of a semi-intrusive (SI) method allowing the computation of statistics of linear and non linear PDEs solutions. This method shows to be very efficient to deal with probability density function of whatsoever form, long-term integration and discontinuities in stochastic space. Given a stochastic PDE where randomness is defined on ?, starting from (i) a description of the solution in term of a space variables, (ii) a numerical scheme defined for any event ??? and (iii) a (family) of random variables that may be correlated, the solution is numerically described by its conditional expectancies of point values or cell averages and its evaluation constructed from the deterministic scheme. One of the tools is a tessellation of the random space as in finite volume methods for the space variables. Then, using these conditional expectancies and the geometrical description of the tessellation, a piecewise polynomial approximation in the random variables is computed using a reconstruction method that is standard for high order finite volume space, except that the measure is no longer the standard Lebesgue measure but the probability measure. This reconstruction is then used to formulate a scheme on the numerical approximation of the solution from the deterministic scheme. This new approach is said semi-intrusive because it requires only a limited amount of modification in a deterministic solver to quantify uncertainty on the state when the solver includes uncertain variables. The effectiveness of this method is illustrated for a modified version of KraichnanOrszag three-mode problem where a discontinuous pdf is associated to the stochastic variable, and for a nozzle flow with shocks. The results have been analyzed in terms of accuracy and probability measure flexibility. Finally, the importance of the probabilistic reconstruction in the stochastic space is shown up on an example where the exact solution is computable, the viscous Burgers equation.
Self-Assembling Sup-porosity: The Effect On Fluid Flow And Seismic Wave Propagation
Pyrak-Nolte, Laura J. [Purdue University
2013-04-27T23:59:59.000Z
Fractures and joints in the field often contain debris within the void spaces. Debris originates from many different mechanisms: organic and/or inorganic chemical reactions/mineralization, sediment transport, formation of a fracture, mechanical weathering or combinations of these processes. In many cases, the presence of debris forms a ??sub-porosity? within the fracture void space. This sub-porosity often is composed of material that differs from the fracture walls in mineralogy and morphology. The ??sub-porosity? may partially fill voids that are on the order of hundreds of microns and thereby reduce the local porosity to lengths scales on the order of sub-microns to tens of microns. It is quite clear that a sub-porosity affects fracture porosity, permeability and storativity. What is not known is how the existence/formation of a sub-porosity affects seismic wave propagation and consequently our ability to probe changes in the subsurface caused by the formation or alteration of a sub-porosity. If seismic techniques are to be developed to monitor the injection and containment of phases in sequestration reservoirs or the propping of hydraulically induced fracture to enhance oil & gas production, it is important to understand how a sub-porosity within a fracture affects macroscopic seismic and hydraulic measurements. A sub-porosity will directly affect the interrelationship between the seismic and hydraulic properties of a fracture. This reports contains the results of the three main topics of research that were performed (1) to determine the effect of a sub-porosity composed of spherical grains on seismic wave propagation across fractures, (2) to determine the effect of biofilm growth in pores and between grains on seismic wave propagation in sediment, and (3) to determine the effect of the scale of observation (field-of-view) on monitoring alteration the pore space within a fracture caused by reactive flow. A brief summary of the results for each topic is contained in the report and the full details of the research and approach are contained in the publications found in the Attachment section of this report. A list of presentation and publications of all work associated with this grant is also provided.
Passive Acoustic Detection of Wind Turbine In-Flow Conditions for Active Control and Optimization
Murray, Nathan E.
2012-03-12T23:59:59.000Z
Wind is a significant source of energy; however, the human capability to produce electrical energy still has many hurdles to overcome. One of these is the unpredictability of the winds in the atmospheric boundary layer (ABL). The ABL is highly turbulent in both stable and unstable conditions (based on the vertical temperature profile) and the resulting fluctuations can have a dramatic impact on wind turbine operation. Any method by which these fluctuations could be observed, estimated, or predicted could provide a benefit to the wind energy industry as a whole. Based on the fundamental coupling of velocity fluctuations to pressure fluctuations in the nearly incompressible flow in the ABL, This work hypothesizes that a ground-based array of infrasonic pressure transducers could be employed to estimate the vertical wind profile over a height relevant for wind turbines. To analyze this hypothesis, experiments and field deployments were conducted. Wind tunnel experiments were performed for a thick turbulent boundary layer over a neutral or heated surface. Surface pressure and velocity probe measurements were acquired simultaneously. Two field deployments yielded surface pressure data from a 49 element array. The second deployment at the Reese Technology Center in Lubbock, TX, also included data from a smaller aperture, 96-element array and a 200-meter tall meteorological tower. Analysis of the data successfully demonstrated the ability to estimate the vertical velocity profile using coherence data from the pressure array. Also, dynamical systems analysis methods were successful in identifying and tracking a gust type event. In addition to the passive acoustic profiling method, this program also investigated a rapid response Doppler SODAR system, the optimization of wind turbine blades for enhanced power with reduced aeroacoustic noise production, and the implementation of a wireless health monitoring system for the wind turbine blades. Each of these other objectives was met successfully. The use of phase unwrapping applied to SODAR data was found to yield reasonable results for per-pulse measurements. A health monitoring system design analysis was able to demonstrate the ability to use a very small number of sensors to monitor blade health based on the blade's overall structural modes. Most notable was the development of a multi-objective optimization methodology that successfully yielded an aerodynamic blade design that produces greater power output with reduced aerodynamic loading noise. This optimization method could be significant for future design work.
Selective evaporation of focusing fluid in two-fluid hydrodynamic print head.
Keicher, David M.; Cook, Adam W.
2014-09-01T23:59:59.000Z
The work performed in this project has demonstrated the feasibility to use hydrodynamic focusing of two fluid steams to create a novel micro printing technology for electronics and other high performance applications. Initial efforts focused solely on selective evaporation of the sheath fluid from print stream provided insight in developing a unique print head geometry allowing excess sheath fluid to be separated from the print flow stream for recycling/reuse. Fluid flow models suggest that more than 81 percent of the sheath fluid can be removed without affecting the print stream. Further development and optimization is required to demonstrate this capability in operation. Print results using two-fluid hydrodynamic focusing yielded a 30 micrometers wide by 0.5 micrometers tall line that suggests that the cross-section of the printed feature from the print head was approximately 2 micrometers in diameter. Printing results also demonstrated that complete removal of the sheath fluid is not necessary for all material systems. The two-fluid printing technology could enable printing of insulated conductors and clad optical interconnects. Further development of this concept should be pursued.
Marinca, Vasile
2015-01-01T23:59:59.000Z
In this paper, Optimal Homotopy Perturbation Method (OHPM) is employed to determine an analytic approximate solutions for nonlinear MHD Jeffery-Hamel flow and heat transfer problem. The Navier-Stokes equations, taking into account Maxwell's electromagnetism and heat transfer lead to two nonlinear ordinary differential equations. The obtained results by means of OHPM show a very good agreement in comparison with the numerical results and with Homotopy Perturbation Method (HPM).
Wisconsin at Madison, University of
This is a 1D model of an active magnetic regenerative refrigerator (AMRR) that was developed of an Active Magnetic Regenerator Refrigerator 1. Governing Equations Figure 1 shows a schematic of an active in MATLAB. The model uses cycle inputs such as the fluid mass flow and magnetic field profiles, fluid
Barran, Brian Arthur
2006-08-16T23:59:59.000Z
, are modified to support a nonuniform simulation grid. In addition, infinite fluid boundary conditions are introduced that allow fluid to flow freely into or out of the simulation domain to achieve the effect of large, boundary free bodies of fluid. Finally, a...
Abdou, Mohamed
sufficiently large heat transfer using high Prandtl number fluid coolant, high turbulence is required, and the heat transfer characteristics of low Prandtl number fluids are con heat transfer (low film temperature drop) to cool first wall structures. In order to obtain
Abbott, Mark W. [Flowserve Corporation, 1978 Foreman Drive Cookeville, TN 38506 (United States)] [Flowserve Corporation, 1978 Foreman Drive Cookeville, TN 38506 (United States)
2013-07-01T23:59:59.000Z
Throughout power generation, delivery and waste remediation, the ability to control process streams in difficult or impossible locations becomes increasingly necessary as the complexity of processes increases. Example applications include radioactive environments, inside concrete installations, buried in dirt, or inside a shielded or insulated pipe. In these situations, it is necessary to implement innovative solutions to tackle such issues as valve maintenance, valve control from remote locations, equipment cleaning in hazardous environments, and flow stream analysis. The Extended Sleeve family of products provides a scalable solution to tackle some of the most challenging applications in hazardous environments which require flow stream control and monitoring. The Extended Sleeve family of products is defined in three groups: Extended Sleeve (ESV), Extended Bonnet (EBV) and Instrument Enclosure (IE). Each of the products provides a variation on the same requirements: to provide access to the internals of a valve, or to monitor the fluid passing through the pipeline through shielding around the process pipe. The shielding can be as simple as a grout filled pipe covering a process pipe or as complex as a concrete deck protecting a room in which the valves and pipes pass through at varying elevations. Extended Sleeves are available between roughly 30 inches and 18 feet of distance between the pipeline centerline and the top of the surface to which it mounts. The Extended Sleeve provides features such as 1.5 inches of adjustment between the pipeline and deck location, internal flush capabilities, automatic alignment of the internal components during assembly and integrated actuator mounting pads. The Extended Bonnet is a shorter fixed height version of the Extended Sleeve which has a removable deck flange to facilitate installation through walls, and is delivered fully assembled. The Instrument Enclosure utilizes many of the same components as an Extended Sleeve, yet allows the installation of process monitoring instruments, such as a turbidity meter to be placed in the flow stream. The basis of the design is a valve body, which, rather than having a directly mounted bonnet has lengths of concentric pipe added, which move the bonnet away from the valve body. The pipe is conceptually similar to an oil field well, with the various strings of casing, and tubing installed. Each concentric pipe provides a required function, such as the outermost pipes, the valve sleeve and penetration sleeve, which provide structural support to the deck flange. For plug valve based designs, the next inner pipe provides compression on the environmental seals at the top of the body to bonnet joint, followed by the innermost pipe which provides rotation of the plug, in the same manner as an extended stem. Ball valve ESVs have an additional pipe to provide compressive loading on the stem packing. Due to the availability of standard pipe grades and weights, the product can be configured to fit a wide array of valve sizes, and application lengths, with current designs as short as seven inches and as tall as 18 feet. Central to the design is the requirement for no special tools or downhole tools to remove parts or configure the product. Off the shelf wrenches, sockets or other hand tools are all that is required. Compared to other products historically available, this design offers a lightweight option, which, while not as rigidly stiff, can deflect compliantly under extreme seismic loading, rather than break. Application conditions vary widely, as the base product is 316 and 304 stainless steel, but utilizes 17-4PH, and other allows as needed based on the temperature range and mechanical requirements. Existing designs are installed in applications as hot as 1400 deg. F, at low pressure, and separately in highly radioactive environments. The selection of plug versus ball valve, metal versus soft seats, and the material of the seals and seats is all dependent on the application requirements. The design of the Extended Sleeve family of products provid
Miller, Jan D; Hupka, Jan; Aranowski, Robert
2012-11-20T23:59:59.000Z
A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.
Hoff, Brian D.; Johnson, Kris William; Algrain, Marcelo C.; Akasam, Sivaprasad
2006-06-06T23:59:59.000Z
A method of controlling the delivery of fluid to an engine includes receiving a fuel flow rate signal. An electric pump is arranged to deliver fluid to the engine. The speed of the electric pump is controlled based on the fuel flow rate signal.
Lavaei, Javad
of the solution of the power flow problem, and (ii) the non-negativity of the locational marginal prices. Partial
Shape optimized headers and methods of manufacture thereof
Perrin, Ian James
2013-11-05T23:59:59.000Z
Disclosed herein is a shape optimized header comprising a shell that is operative for collecting a fluid; wherein an internal diameter and/or a wall thickness of the shell vary with a change in pressure and/or a change in a fluid flow rate in the shell; and tubes; wherein the tubes are in communication with the shell and are operative to transfer fluid into the shell. Disclosed herein is a method comprising fixedly attaching tubes to a shell; wherein the shell is operative for collecting a fluid; wherein an internal diameter and/or a wall thickness of the shell vary with a change in pressure and/or a change in a fluid flow rate in the shell; and wherein the tubes are in communication with the shell and are operative to transfer fluid into the shell.
Film boiling on the inside of vertical tubes with upward flow of the fluid at low qualities
Dougall, R. S.
1963-01-01T23:59:59.000Z
Flow regimes, local heat transfer coefficients, and temperature distributions along the wall have been studied for film boiling inside a vertical tube with upward flow of a saturated liquid. The area of interest has been ...
Khan, Arshad; Khan, Ilyas; Shafie, Sharidan [Faculty of Science, Universiti Teknologi Malaysia (Malaysia)
2014-06-19T23:59:59.000Z
This article studies the radiation and porosity effects on the unsteady magnetohydrodynamic free convection flow of an incompressible viscous fluid past an infinite vertical plate that applies a shear stress f(t) to the fluid. Conjugate phenomenon of heat and mass transfer is considered. General solutions of the dimensionless governing equations along with imposed initial and boundary conditions are determined using Laplace transform technique. The solution of velocity is presented as a sum of mechanical and non mechanical parts. These solutions satisfy all imposed initial and boundary conditions and reduce to some known solutions from the literature as special cases. The results for embedded parameters are shown graphically. Numerical results for skin friction, Nusselt number and Sherwood number are computed and presented in tabular forms.
Optimizing control flow in loops using interval anddependence analysis
Ghodrat, Mohammad Ali; Givargis, Tony; Nicolau, Alex
2009-01-01T23:59:59.000Z
graphics mpgdec-initdec mpgenc-vh?lter mp3-psych mp3-align mpgenc-idct mpgdec-vh?lter Optimizing control ?graphics mpgdec-initdec mpgenc-vh?lter mp3-psych mp3-align mpgenc-idct mpgdec-vh?lter Optimizing control ?graphics mpgdec-initdec mpgenc-vh?lter mp3-psych mp3-align mpgenc-idct mpgdec-vh?lter Optimizing control ?
McHugh, P.R.
1995-10-01T23:59:59.000Z
Fully coupled, Newton-Krylov algorithms are investigated for solving strongly coupled, nonlinear systems of partial differential equations arising in the field of computational fluid dynamics. Primitive variable forms of the steady incompressible and compressible Navier-Stokes and energy equations that describe the flow of a laminar Newtonian fluid in two-dimensions are specifically considered. Numerical solutions are obtained by first integrating over discrete finite volumes that compose the computational mesh. The resulting system of nonlinear algebraic equations are linearized using Newton`s method. Preconditioned Krylov subspace based iterative algorithms then solve these linear systems on each Newton iteration. Selected Krylov algorithms include the Arnoldi-based Generalized Minimal RESidual (GMRES) algorithm, and the Lanczos-based Conjugate Gradients Squared (CGS), Bi-CGSTAB, and Transpose-Free Quasi-Minimal Residual (TFQMR) algorithms. Both Incomplete Lower-Upper (ILU) factorization and domain-based additive and multiplicative Schwarz preconditioning strategies are studied. Numerical techniques such as mesh sequencing, adaptive damping, pseudo-transient relaxation, and parameter continuation are used to improve the solution efficiency, while algorithm implementation is simplified using a numerical Jacobian evaluation. The capabilities of standard Newton-Krylov algorithms are demonstrated via solutions to both incompressible and compressible flow problems. Incompressible flow problems include natural convection in an enclosed cavity, and mixed/forced convection past a backward facing step.
Bianco, Ronald
2013-12-02T23:59:59.000Z
have an increased localization toward the boundaries of the gouge layer (type III), and no occurrence of distributed (type I) shear. Systems with lower N and k show liquefaction events. Liquefaction events originate from increases in fluid pressure...
Jain, Antone Kumar
2009-01-01T23:59:59.000Z
We present a discrete element model for simulating, at the grain scale, gas migration in brine-saturated deformable media. We rigorously account for the presence of two fluids in the pore space by incorporating forces on ...
A thermodynamic hypothesis regarding optimality principles for flow processes in geosystems
Liu, Hui-Hai
2015-01-01T23:59:59.000Z
a review of the maximum entropy production principle. RevSeleznev VD (2006) Maximum entropy pro- duction principle inexpenditure rate Maximum entropy production Optimality
Ulbrich, Michael
control problems that are governed by multiphase multicomponent flow in porous media. The concrete in porous media. The objective is, e.g., to maximize the amount of trapped CO2 in an underground reservoir/FV methods for multiphase multicomponent flows in porous media we refer to [11] and references therein
Stocker, H.
2012-01-01T23:59:59.000Z
Flow in Central High Energy Nuclear Collisions H. Stockera,theoretical models of high energy nuclear collisions andunder Contract High energy nuclear collisions offer a unique
Finite element simulation of electrorheological fluids
Rhyou, Chanryeol, 1973-
2005-01-01T23:59:59.000Z
Electrorheological (ER) fluids change their flow properties dramatically when an electric field is applied. These fluids are usually composed of dispersions of polarizable particles in an insulating base fluid or composed ...
On-chip interconnection architecture optimization using a multicommodity flow approach
Hu, Yuanfang
2007-01-01T23:59:59.000Z
to re- duce its energy and switch area-e?ciency. Theectively reduce energy and switch area usage of FPGA routingectively optimize the energy and switch area of FPGA routing
Liu, G.; Liu, M.
2006-01-01T23:59:59.000Z
This paper presents a new building energy monitoring and pump speed control method. The pump speed is controlled to maintain the system resistance at an optimized value to approach the best pump efficiency and save pump power. The system resistance...
Thermal Storage and Advanced Heat Transfer Fluids (Fact Sheet)
Not Available
2010-08-01T23:59:59.000Z
Fact sheet describing NREL CSP Program capabilities in the area of thermal storage and advanced heat transfer fluids: measuring thermophysical properties, measuring fluid flow and heat transfer, and simulating flow of thermal energy and fluid.
Thomas, Brian G.
-mail:barco@labein.es Jose Luis Arana University of Basque Country C/Alameda de Urkijo S/N 48013-Bilbao(Vizcaya)-Spain Fax:+34-94-601-4180 E-mail:jl.arana@ehu.es Key words: Mold powder, Lubrication, Overflow, Slag rim, Fluid
Ultrasonic Fluid Quality Sensor System
Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)
2003-10-21T23:59:59.000Z
A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.
Ultrasonic fluid quality sensor system
Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)
2002-10-08T23:59:59.000Z
A system for determining the composition of a multiple-component fluid and for determining linear flow comprising at least one sing-around circuit that determines the velocity of a signal in the multiple-component fluid and that is correlatable to a database for the multiple-component fluid. A system for determining flow uses two of the inventive circuits, one of which is set at an angle that is not perpendicular to the direction of flow.
Morozov, Victor (Manassas, VA)
2011-01-18T23:59:59.000Z
A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.
Using the NOABL flow model and mathematical optimization as a micrositing tool
Wegley, H.L.; Barnard, J.C.
1986-11-01T23:59:59.000Z
This report describes the use of an improved mass-consistent model that is intended for diagnosing wind fields in complex terrain. The model was developed by merging an existing mass-consistent model, the NOABL model, with an optimization procedure. The optimization allows objective calculation of important model input parameters that previously had been supplied through guesswork; in this manner, the accuracy of the calculated winds has been greatly increased. The report covers such topics as the software structure of the model, assembling an input file, processing the model's output, and certain cautions about the model's operation. The use of the model is illustrated by a test case.
Tam, Daniel See Wai, 1980-
2004-01-01T23:59:59.000Z
The design of future light aerospace structures will require numerical tools to accurately describe the strongly coupled dynamics of the interactions between a light structure and a flow surrounding it. Specific examples ...
Rutqvist, J.
2011-01-01T23:59:59.000Z
Analytical Methods in Geomechanics 17, 577598. Liu, H.H. ,J.E. , 2003. Coupled geomechanics and reservoir simulation.coupling porous flow and geomechanics. Society of Petroleum
M. G. McKellar; J. E. O'Brien; E. A. Harvego; J. S. Herring
2007-11-01T23:59:59.000Z
This report presents results from the development and optimization of a reference commercialscale high-temperature electrolysis (HTE) plant for hydrogen production. The reference plant design is driven by a high-temperature helium-cooled reactor coupled to a direct Brayton power cycle. The reference design reactor power is 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 540 C and 900C, respectively. The electrolysis unit used to produce hydrogen consists of 4.176 10 6 cells with a per-cell active area of 225 cm2. A nominal cell area-specific resistance, ASR, value of 0.4 Ohmcm2 with a current density of 0.25 A/cm2 was used, and isothermal boundary conditions were assumed. The optimized design for the reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes an air-sweep system to remove the excess oxygen that is evolved on the anode side of the electrolyzer. The inlet air for the air-sweep system is compressed to the system operating pressure of 5.0 MPa in a four-stage compressor with intercooling. The overall system thermal-to-hydrogen production efficiency (based on the low heating value of the produced hydrogen) is 49.07% at a hydrogen production rate of 2.45 kg/s with the high-temperature helium-cooled reactor concept. The information presented in this report is intended to establish an optimized design for the reference nuclear-driven HTE hydrogen production plant so that parameters can be compared with other hydrogen production methods and power cycles to evaluate relative performance characteristics and plant economics.
Fluid&ParticulateSystems 424514/2010
Zevenhoven, Ron
.zevenhoven@abo.fi 2Fluid&ParticulateSystems 424514/2010 Fluid&ParticulateSystems A424514/2014 2.1 Flow tube sections / Turku Finland RoNz 3 Fluid Flow in Tube Systems loss 2 2 1 pump 2 2 1 ppwzgppwzg outoutoutoutininininloss,311 ' 3 ppzgp 2loss,322 ' 3 ppzgp 210 VVV For a fully developed turbulent flow (horizontal
Recent developments in model-based optimization and control of subsurface flow
Van den Hof, Paul
; identifiability; model reduction. 1. INTRODUCTION The production of oil and gas from petroleum reservoirs the pores of subsurface rock lay- ers. The production life of a petroleum reservoir generally lasts a number configurations and production strategies, but an emerging use is in the 'real-time' optimization and control
Dynamics-aware Optimal Power Flow Enrique Mallada and Ao Tang
Tang, A. Kevin
oscillations and voltage stability margins. This leads to two novel optimization problems that can find operation points which minimize oscillations or maximize voltage stability margins, and make apparent and small signal oscillation studies because the voltage collapse margin and stability of the operating
Approximating an Optimal Production Policy in a Continuous Flow Line: Recurrence and Asymptotic
Vzquez-Abad, Felisa J.
, production planning and schedul ing, producetostock, buffer size, buffer control, JIT systemsprone tandem machines. The production is regulated by a continuous version of buffer control. Our goal that for each feasible machine state, the optimal production control policy is to move the inventory levels
Qin, Wensheng
of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Iran d Imperial Oil Limited, Supply additive, and the process was optimized in this study using response surface methodology. A model biodiesel process [1,2]. Hence a huge amount of glycerol is expected on the market in near future. Due
Improving electricity production in tubular microbial fuel cells through optimizing the anolyte h l i g h t s " The spiral spacers improve electricity production in tubular microbial fuel cells fuel cells Spiral spacers Energy Wastewater treatment a b s t r a c t The use of spiral spacers
Optimization Online - Structural optimization of the Ziegler's ...
Oleg N. Kirillov
2010-12-24T23:59:59.000Z
Dec 24, 2010 ... Abstract: Structural optimization of non-conservative systems with ... with important applications in fluid-structure interactions, friction-induced...
Linear conic optimization for nonlinear optimal control
2014-07-07T23:59:59.000Z
Jul 7, 2014 ... This linear transport equation is classical in fluid mechanics, statistical ... define a relaxed optimal control problem as an LP in the cone of non-.
Optimal investment on finite horizon with random discrete order flow in illiquid markets
Paris-Sud XI, Universit de
both on trading and observation of the assets. For example, in power markets, trading occurs through at any time but trading occurs more frequently near a terminal horizon. The investor can observe and trade the risky asset only at exogenous random times corresponding to the order flow given
Optimization of Cricket-inspired, Biomimetic Artificial Hair Sensors for Flow Sensing
Izadi, N; Floris, J; Krijnen, G
2008-01-01T23:59:59.000Z
High density arrays of artificial hair sensors, biomimicking the extremely sensitive mechanoreceptive filiform hairs found on cerci of crickets have been fabricated successfully. We assess the sensitivity of these artificial sensors and present a scheme for further optimization addressing the deteriorating effects of stress in the structures. We show that, by removing a portion of chromium electrodes close to the torsional beams, the upward lift at the edges of the membrane due to the stress, will decrease hence increase the sensitivity.
A STOCHASTIC METHOD FOR MODELING FLUID DISPLACEMENT IN PETROLEUM RESERVOIRS
Anderson, C.
2011-01-01T23:59:59.000Z
FLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andFLUID DISPLACEMENT IN PETROLEUM RESERVOIRS C. Anderson andachieve optimal recovery of petroleum from a reservoir, it
Muralidharan, Vivek
2004-11-15T23:59:59.000Z
pressure of 500 psi................................................................33 3.16 The average flow rate comparison between laboratory and simulation results at 5 cc/min and each different overburden pressure.............................35... .........................................................................................................87 xiii FIGURE Pa ge 5.28 Sample scans taken along the length of the core with 500 psi overburden pressure...
Yang, Cher-Chiang
2008-05-05T23:59:59.000Z
............................................................................................................... 25 3.2.4. Starting FlowLab ...................................................................................................................... 26 3.2.5. Geometry Settings... OF THE PROGRAMMING....................................................................... 52 v List of Figures FIGURE 2.1 ? COST AND TIME RELATIONSHIP WITH RESPECT TO CFD AND WIND TUNNELS............................. 5 FIGURE 2.2 - BOEING 777 DESIGN...
A coupled volume-of-fluid and level set (VOSET) method for computing incompressible two-phase flows
Frey, Pascal
& Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, PR China a r t i c l e i n f o processes such as chemical reactor, power plant, copper refining and internal combustion engine developed to simulate complex two-phase flow problems. The most important methods include the front tracking
Bahrami, Majid
the properties of porous media e.g. permeability. This can be achieved by using Darcy's equation which assumes is empirical, convenient, and widely accepted. However, Darcy's equation holds when flow is in creeping regime [4]. To use Darcy's equation we need to know the permeability of the medium beforehand. Permeability
Chuang, Y.; Haldeman, W.R.; Rasmussen, T.C.; Evans, D.D. [Arizona Univ., Tucson, AZ (USA). Dept. of Hydrology and Water Resources
1990-02-01T23:59:59.000Z
Laboratory techniques are developed that allow concurrent measurement of unsaturated matrix hydraulic conductivity and fracture transmissivity of fractured rock blocks. Two Apache Leap tuff blocks with natural fractures were removed from near Superior, Arizona, shaped into rectangular prisms, and instrumented in the laboratory. Porous ceramic plates provided solution to block tops at regulated pressures. Infiltration tests were performed on both test blocks. Steady flow testing of the saturated first block provided estimates of matrix hydraulic conductivity and fracture transmissivity. Fifteen centimeters of suction applied to the second block top showed that fracture flow was minimal and matrix hydraulic conductivity was an order of magnitude less than the first block saturated matrix conductivity. Coated-wire ion-selective electrodes monitored aqueous chlorided breakthrough concentrations. Minute samples of tracer solution were collected with filter paper. The techniques worked well for studying transport behavior at near-saturated flow conditions and also appear to be promising for unsaturated conditions. Breakthrough curves in the fracture and matrix, and a concentration map of chloride concentrations within the fracture, suggest preferential flows paths in the fracture and substantial diffusion into the matrix. Average travel velocity, dispersion coefficient and longitudinal dispersivity in the fracture are obtained. 67 refs., 54 figs., 23 tabs.
Abu-Hassoun, Amer H.
2009-05-15T23:59:59.000Z
and fractures were treated as two systems. Reservoir management practices and decisions should be very carefully reviewed and executed in this dual continuum reservoir based on the results of this work. Studying this dual media flow behavior is vital for better...
Georgiou, Georgios
2007-01-01T23:59:59.000Z
plastics Maria Chatziminaa, Christos Xenophontosa, Georgios C. Georgioua,, Ioannis Argyropaidasb, Evan plastics for various values of the diameter ratio, using the regularized constitutive equation proposed, 1984]. © 2006 Elsevier B.V. All rights reserved. Keywords: Annular Poiseuille flow; Bingham plastic
Chance Constrained Optimal Power Flow: Risk-Aware Network Control under Uncertainty
Bienstock, Daniel; Harnett, Sean
2012-01-01T23:59:59.000Z
When uncontrollable resources fluctuate, Optimum Power Flow (OPF), routinely used by the electric power industry to re-dispatch hourly controllable generation (coal, gas and hydro plants) over control areas of transmission networks, can result in grid instability, and, potentially, cascading outages. This risk arises because OPF dispatch is computed without awareness of major uncertainty, in particular fluctuations in renewable output. As a result, grid operation under OPF with renewable variability can lead to frequent conditions where power line flow ratings are significantly exceeded. Such a condition, which is borne by simulations of real grids, would likely resulting in automatic line tripping to protect lines from thermal stress, a risky and undesirable outcome which compromises stability. Smart grid goals include a commitment to large penetration of highly fluctuating renewables, thus calling to reconsider current practices, in particular the use of standard OPF. Our Chance Constrained (CC) OPF correct...
Multiphase fluid characterization system
Sinha, Dipen N.
2014-09-02T23:59:59.000Z
A measurement system and method for permitting multiple independent measurements of several physical parameters of multiphase fluids flowing through pipes are described. Multiple acoustic transducers are placed in acoustic communication with or attached to the outside surface of a section of existing spool (metal pipe), typically less than 3 feet in length, for noninvasive measurements. Sound speed, sound attenuation, fluid density, fluid flow, container wall resonance characteristics, and Doppler measurements for gas volume fraction may be measured simultaneously by the system. Temperature measurements are made using a temperature sensor for oil-cut correction.
Marcos, Ph.D. Massachusetts Institute of Technology
2011-01-01T23:59:59.000Z
Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...
Flow control techniques for real-time media applications in best-effort networks using fluid models
Konstantinou, Apostolos
2004-11-15T23:59:59.000Z
at the application layer. An end-to-end ?uid model is used, including the source bu?er, the network and the destination bu?er. Traditional con- trol techniques, along with more advanced adaptive predictive control methods, are considered in order to provide... OF THE END-TO-END FLOW TRANSPORT SYSTEM : : : : : : : : : : : : : : : : : : : : : : 25 A. Source Bu?er Model . . . . . . . . . . . . . . . . . . . . . 25 B. Network Dynamic Model . . . . . . . . . . . . . . . . . . . 27 1. Time-Varying Time Delay Model...
Bahrami, Majid
7-22 7-58 A commercial refrigerator with R-134a as the working fluid is considered. The evaporator inlet and exit states are specified. The mass flow rate of the refrigerant and the rate of heat rejected are to be determined. Assumptions 1 The refrigerator operates steadily. 2 The kinetic and potential energy changes
Ewing, Richard E.
reservoir conditions, such as partially filled fractures. Introduction Naturally fractured karst reservoirsSPE 110778 Multiscale Methods for Modeling Fluid Flow Through Naturally Fractured Carbonate Karst Reservoirs P. Popov, G. Qin, L. Bi, Y. Efendiev, R. Ewing, Institute for Scientific Computation, Texas A
Ultrasonic flow metering system
Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)
2002-01-01T23:59:59.000Z
A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.
IMPROVING ENERGY EFFICIENCY VIA OPTIMIZED CHARGE MOTION AND SLURRY FLOW IN PLANT SCALE SAG MILLS
Raj K. Rajamani; Sanjeeva Latchireddi; Sravan K. Prathy; Trilokyanath Patra
2005-12-01T23:59:59.000Z
The U.S. mining industry operates approximately 80 semi-autogenesis grinding mills (SAG) throughout the United States. Depending on the mill size the SAG mills draws between 2 MW and 17 MW. The product from the SAG mill is further reduced in size using pebble crushers and ball mills. Hence, typical gold or copper ore requires between 2.0 and 7.5 kWh per ton of energy to reduce the particle size. Considering a typical mining operation processes 10,000 to 100,000 tons per day the energy expenditure in grinding is 50 percent of the cost of production of the metal. A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Kennecott Utah Copper Corporation, Process Engineering Resources Inc. and others. In the current project, Cortez Gold Mines played a key role in facilitating the 26-ft SAG mill at Cortez as a test mill for this study. According to plant personnel, there were a number of unscheduled shut downs to repair broken liners and the mill throughput fluctuated depending on ore type. The University team had two softwares, Millsoft and FlowMod to tackle the problem. Millsoft is capable of simulating the motion of charge in the mill. FlowMod calculates the slurry flow through the grate and pulp lifters. Based on this data the two models were fine-tuned to fit the Cortez SAG will. In the summer of 2004 a new design of shell lifters were presented to Cortez and in September 2004 these lifters were installed in the SAG mill. By December 2004 Cortez Mines realized that the SAG mill is drawing approximately 236-kW less power than before while maintaining the same level of production. In the first month there was extreme cycling and operators had to learn more. Now the power consumption is 0.3-1.3 kWh/ton lower than before. The actual SAG mill power draw is 230-370 kW lower. Mill runs 1 rpm lesser in speed on the average. The re-circulation to the cone crusher is reduced by 1-10%, which means more efficient grinding of critical size material is taking place in the mill. All of the savings have resulted in reduction of operating cost be about $0.023-$0.048/ ton.
Isotopic Analysis- Fluid At Dixie Valley Geothermal Area (Kennedy...
geothermal resources with deep, fault hosted permeable fluid flow pathways and the helium Isotopic composition of the surface fluids. The authors suggest that helium isotopes...
Angel, S.M.
1987-02-27T23:59:59.000Z
Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.
Optimization of electrode characteristics for the Br?/H? redox flow cell
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Van Nguyen, Trung
2015-01-01T23:59:59.000Z
The Br?/H? redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and () electrode architecture are investigated. Increasing hydrogen pressure and depositing the () catalyst layer on the membrane instead of on the carbon-paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm-2 and a peak power density of 1.4 W cm-2. Maximum energy efficiencymoreof 79% is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt () electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.less
Optimization of electrode characteristics for the Br2/H2 redox flow cell
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Nguyen, Trung V.
2014-10-01T23:59:59.000Z
The Br2/H2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (?) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (?) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm?2 and a peak power density of 1.4 W cm?2. Maximum energymoreefficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt (?) electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.less
Optimization of electrode characteristics for the Br2/H2 redox flow cell
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tucker, Michael C.; Cho, Kyu Taek; Weber, Adam Z.; Lin, Guangyu; Nguyen, Trung V.
2014-10-01T23:59:59.000Z
The Br2/H2 redox flow cell shows promise as a high-power, low-cost energy storage device. The effect of various aspects of material selection, processing, and assembly of electrodes on the operation, performance, and efficiency of the system is determined. In particular, (+) electrode thickness, cell compression, hydrogen pressure, and (?) electrode architecture are investigated. Increasing hydrogen pressure and depositing the (?) catalyst layer on the membrane instead of on the carbon paper backing layers have a large positive impact on performance, enabling a limiting current density above 2 A cm?2 and a peak power density of 1.4 W cm?2. Maximum energy efficiency of 79 % is achieved. In addition, the root cause of limiting-current behavior in this system is elucidated, where it is found that Br? reversibly adsorbs at the Pt (?) electrode for potentials exceeding a critical value, and the extent of Br? coverage is potential-dependent. This phenomenon limits maximum cell current density and must be addressed in system modeling and design. These findings are expected to lower system cost and enable higher efficiency.
Ying, D.H.S.; Sivasubramanian, R.; Moujaes, S.F.; Givens, E.N.
1982-04-01T23:59:59.000Z
A commercial coal liquefaction plant will employ vertical tubular reactors feeding slurry and gas concurrently upward through these vessels. In the SRC-I plant design the reactor is essentially an empty vessel with only a distributor plate located near the inlet. Because the commercial plant represents a considerable scale-up over Wilsonville or any pilot plant, this program addressed the need for additional data on behavior of three phase systems in large vessels. Parameters that were investigated in this program were studied at conditions that relate directly to projected plant operating conditions. The fluid dynamic behavior of the three-phase upflow system was studied by measuring gas and slurry holdup, liquid dispersion, solids suspension and solids accumulation. The dependent parameters are gas and liquid velocities, solid particle size, solids concentration, liquid viscosity, liquid surface tension and inlet distributor. Within the range of liquid superficial velocity from 0.0 to 0.5 ft/sec, gas holdup is found to be independent of liquid flow which agrees with other investigators. The results also confirm our previous finding that gas holdup is independent of column diameter when the column diameter is 5 inches or larger. The gas holdup depends strongly on gas flow rate; gas holdup increases with increasing gas velocity. The effect of solids particles on gas holdup depends on the gas flow rate. Increasing liquid viscosity and surface tension reduce gas holdup which agrees with other investigators. Because of the complexity of the system, we could not find a single correlation to best fit all the data. The degree of liquid backmixing markedly affects chemical changes occurring in the dissolver, such as sulfur removal, and oil and distillate formation.
Meixler, Lewis D. (East Windsor, NJ)
1993-01-01T23:59:59.000Z
The low flow monitor provides a means for determining if a fluid flow meets a minimum threshold level of flow. The low flow monitor operates with a minimum of intrusion by the flow detection device into the flow. The electrical portion of the monitor is externally located with respect to the fluid stream which allows for repairs to the monitor without disrupting the flow. The electronics provide for the adjustment of the threshold level to meet the required conditions. The apparatus can be modified to provide an upper limit to the flow monitor by providing for a parallel electronic circuit which provides for a bracketing of the desired flow rate.
Doughty, C.; Tsang, C.-F.; Hatanaka, K.; Yabuuchi, S.; Kurikami, H.
2007-08-01T23:59:59.000Z
The flowing fluid electric conductivity (FFEC) loggingmethod is an efficient way to provide information on the depths,salinities, and transmissivities of individual conductive featuresintercepted by a borehole, without the use of specialized probes. Usingit in a multiple-flow-rate mode allows, in addition, an estimate of theinherent "far-field" pressure heads in each of the conductive features.The multi-rate method was successfully applied to a 500-m borehole in agranitic formation and reported recently. The present paper presents theapplication of the method to two zones within a 1000-m borehole insedimentary rock, which produced, for each zone, three sets of logs atdifferent pumping rates, each set measured over a period of about oneday. The data sets involve a number of complications, such as variablewell diameter, free water table decline in the well, and effects ofdrilling mud. To analyze data from this borehole, we apply varioustechniques that have been developed for analyzing FFEC logs:direct-fitting, mass-integral, and the multi-rate method mentioned above.In spite of complications associated with the tests, analysis of the datais able to identify 44 hydraulically conducting fractures distributedover the depth interval 150-775 meters below ground surface. Thesalinities (in FEC), and transmissivities and pressure heads (indimensionless form) of these 44 features are obtained and found to varysignificantly among one another. These results are compared with datafrom eight packer tests with packer intervals of 10-80 m, which wereconducted in this borehole over the same depth interval. They are foundto be consistent with these independent packer-test data, thusdemonstrating the robustness of the FFEC logging method under non-idealconditions.
Xiong, Yi [Colorado School of Mines; Fakcharoenphol, Perapon [Colorado School of Mines; Wang, Shihao [Colorado School of Mines; Winterfeld, Philip H. [Colorado School of Mines; Zhang, Keni [Lawrence Berkeley National Laboratory; Wu, Yu-Shu [Colorado School of Mines
2013-12-01T23:59:59.000Z
TOUGH2-EGS-MP is a parallel numerical simulation program coupling geomechanics with fluid and heat flow in fractured and porous media, and is applicable for simulation of enhanced geothermal systems (EGS). TOUGH2-EGS-MP is based on the TOUGH2-MP code, the massively parallel version of TOUGH2. In TOUGH2-EGS-MP, the fully-coupled flow-geomechanics model is developed from linear elastic theory for thermo-poro-elastic systems and is formulated in terms of mean normal stress as well as pore pressure and temperature. Reservoir rock properties such as porosity and permeability depend on rock deformation, and the relationships between these two, obtained from poro-elasticity theories and empirical correlations, are incorporated into the simulation. This report provides the user with detailed information on the TOUGH2-EGS-MP mathematical model and instructions for using it for Thermal-Hydrological-Mechanical (THM) simulations. The mathematical model includes the fluid and heat flow equations, geomechanical equation, and discretization of those equations. In addition, the parallel aspects of the code, such as domain partitioning and communication between processors, are also included. Although TOUGH2-EGS-MP has the capability for simulating fluid and heat flows coupled with geomechanical effects, it is up to the user to select the specific coupling process, such as THM or only TH, in a simulation. There are several example problems illustrating applications of this program. These example problems are described in detail and their input data are presented. Their results demonstrate that this program can be used for field-scale geothermal reservoir simulation in porous and fractured media with fluid and heat flow coupled with geomechanical effects.
Faybishenko, B.; Doughty, C.; Geller, J. [and others
1998-07-01T23:59:59.000Z
Understanding subsurface flow and transport processes is critical for effective assessment, decision-making, and remediation activities for contaminated sites. However, for fluid flow and contaminant transport through fractured vadose zones, traditional hydrogeological approaches are often found to be inadequate. In this project, the authors examine flow and transport through a fractured vadose zone as a deterministic chaotic dynamical process, and develop a model of it in these terms. Initially, the authors examine separately the geometric model of fractured rock and the flow dynamics model needed to describe chaotic behavior. Ultimately they will put the geometry and flow dynamics together to develop a chaotic-dynamical model of flow and transport in a fractured vadose zone. They investigate water flow and contaminant transport on several scales, ranging from small-scale laboratory experiments in fracture replicas and fractured cores, to field experiments conducted in a single exposed fracture at a basalt outcrop, and finally to a ponded infiltration test using a pond of 7 by 8 m. In the field experiments, they measure the time-variation of water flux, moisture content, and hydraulic head at various locations, as well as the total inflow rate to the subsurface. Such variations reflect the changes in the geometry and physics of water flow that display chaotic behavior, which they try to reconstruct using the data obtained. In the analysis of experimental data, a chaotic model can be used to predict the long-term bounds on fluid flow and transport behavior, known as the attractor of the system, and to examine the limits of short-term predictability within these bounds. This approach is especially well suited to the need for short-term predictions to support remediation decisions and long-term bounding studies. View-graphs from ten presentations made at the annual meeting held December 3--4, 1997 are included in an appendix to this report.
Ultrarelativistic fluid dynamics
David W. Neilsen; Matthew W. Choptuik
1999-04-20T23:59:59.000Z
This is the first of two papers examining the critical collapse of spherically symmetric perfect fluids with the equation of state P = (Gamma -1)rho. Here we present the equations of motion and describe a computer code capable of simulating the extremely relativistic flows encountered in critical solutions for Gamma <= 2. The fluid equations are solved using a high-resolution shock-capturing scheme based on a linearized Riemann solver.
Oborny, Michael C. (Albuquerque, NM); Paul, Phillip H. (Livermore, CA); Hencken, Kenneth R. (Pleasanton, CA); Frye-Mason, Gregory C. (Cedar Crest, NM); Manginell, Ronald P. (Albuquerque, NM)
2001-01-01T23:59:59.000Z
A valve for controlling fluid flows. This valve, which includes both an actuation device and a valve body provides: the ability to incorporate both the actuation device and valve into a unitary structure that can be placed onto a microchip, the ability to generate higher actuation pressures and thus control higher fluid pressures than conventional microvalves, and a device that draws only microwatts of power. An electrokinetic pump that converts electric potential to hydraulic force is used to operate, or actuate, the valve.
Variable flexure-based fluid filter
Brown, Steve B.; Colston Jr., Billy W.; Marshall, Graham; Wolcott, Duane
2007-03-13T23:59:59.000Z
An apparatus and method for filtering particles from a fluid comprises a fluid inlet, a fluid outlet, a variable size passage between the fluid inlet and the fluid outlet, and means for adjusting the size of the variable size passage for filtering the particles from the fluid. An inlet fluid flow stream is introduced to a fixture with a variable size passage. The size of the variable size passage is set so that the fluid passes through the variable size passage but the particles do not pass through the variable size passage.
Mechanical Engineering ME 3720 FLUID MECHANICS
Panchagnula, Mahesh
. Fundamentals of fluid flow; fluid statics; systems, and control volumes; continuity, momentum and energy physical model results to prototype 10. Use Moody chart to calculate friction losses in pipe flows 11 equations; dynamic similitude; One-dimensional compressible flow. The objective(s) of this course is (are
ASTROPHYSICAL FLUID DYNAMICS VIA DIRECT STATISTICAL SIMULATION
Tobias, S. M. [Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom); Dagon, K.; Marston, J. B., E-mail: smt@maths.leeds.ac.uk [Department of Physics, Brown University, Providence, RI 02912-1843 (United States)
2011-02-01T23:59:59.000Z
In this paper, we introduce the concept of direct statistical simulation for astrophysical flows. This technique may be appropriate for problems in astrophysical fluids where the instantaneous dynamics of the flows are of secondary importance to their statistical properties. We give examples of such problems including mixing and transport in planets, stars, and disks. The method is described for a general set of evolution equations, before we consider the specific case of a spectral method optimized for problems on a spherical surface. The method is illustrated for the simplest non-trivial example of hydrodynamics and magnetohydrodynamics on a rotating spherical surface. We then discuss possible extensions of the method both in terms of computational methods and the range of astrophysical problems that are of interest.
Adaptive finite element methods for PDE-constrained optimal control problems
Adaptive finite element methods for PDE-constrained optimal control problems R. Becker1 , M. Braack is discretized by a finite element Galerkin method. The accuracy of the discretization is controlled by residual of heat transfer, fluid flow and parameter estimation. The contents of this article is as follows
Fluid-solid-electric lock-in of energy-harvesting piezoelectric flags
Xia, Yifan; Doare, Olivier
2015-01-01T23:59:59.000Z
The spontaneous flapping of a flag in a steady flow can be used to power an output circuit using piezoelectric elements positioned at its surface. Here, we study numerically the effect of inductive circuits on the dynamics of this fluid-solid-electric system and on its energy harvesting efficiency. In particular, a destabilization of the system is identified leading to energy harvesting at lower flow velocities. Also, a frequency lock-in between the flag and the circuit is shown to significantly enhance the system's harvesting efficiency. These results suggest promising efficiency enhancements of such flow energy harvesters through the output circuit optimization.
Zevenhoven, Ron
Introduction to Computational Fluid Dynamics 424512 E #1 - rz Introduction to Computational Fluid Dynamics (iCFD) 424512.0 E, 5 sp / 3 sw 1. Introduction; Fluid dynamics (lecture 1 of 5) Ron Zevenhoven ?bo to Computational Fluid Dynamics 424512 E #1 - rz april 2013 ?bo Akademi Univ - Thermal and Flow Engineering
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS Int. J. Numer. Meth. Fluids 2011; 00:123
Buscaglia, Gustavo C.
, magma chambers, fluidfuel interactions, crude oil recovery, spray cans, sediment transport in riversINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS Int. J. Numer. Meth. Fluids 2011; 00 for the treatment of discontinuous pressures in multifluid flows Roberto F. Ausas1 , Gustavo C. Buscaglia1
Fluid Mixing from Viscous Fingering
Jha, Birendra
Mixing efficiency at low Reynolds numbers can be enhanced by exploiting hydrodynamic instabilities that induce heterogeneity and disorder in the flow. The unstable displacement of fluids with different viscosities, or ...
Alan Black; Arnis Judzis
2004-10-01T23:59:59.000Z
The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit-fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all major preparations for the high pressure drilling campaign. Baker Hughes encountered difficulties in providing additional pumping capacity before TerraTek's scheduled relocation to another facility, thus the program was delayed further to accommodate the full testing program.
Multiple source/multiple target fluid transfer apparatus
Turner, Terry D. (Idaho Falls, ID)
1997-01-01T23:59:59.000Z
A fluid transfer apparatus includes: a) a plurality of orifices for connection with fluid sources; b) a plurality of orifices for connection with fluid targets; c) a set of fluid source conduits and fluid target conduits associated with the orifices; d) a pump fluidically interposed between the source and target conduits to transfer fluid therebetween; e) a purge gas conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass a purge gas under pressure; f) a solvent conduit in fluid communication with the fluid source conduits, fluid target conduits and pump to receive and pass solvent, the solvent conduit including a solvent valve; g) pump control means for controlling operation of the pump; h) purge gas valve control means for controlling operation of the purge gas valve to selectively impart flow of purge gas to the fluid source conduits, fluid target conduits and pump; i) solvent valve control means for controlling operation of the solvent valve to selectively impart flow of solvent to the fluid source conduits, fluid target conduits and pump; and j) source and target valve control means for controlling operation of the fluid source conduit valves and the fluid target conduit valves to selectively impart passage of fluid between a selected one of the fluid source conduits and a selected one of the fluid target conduits through the pump and to enable passage of solvent or purge gas through selected fluid source conduits and selected fluid target conduits.
Ulbrich, Michael
WITH APPLICATIONS TO CO2 SEQUESTRATION IN UNDERGROUND RESERVOIRS MORITZ SIMON AND MICHAEL ULBRICH Abstract. With the target of optimizing CO2 sequestration in underground reservoirs, we investigate constrained optimal the amount of trapped CO2 in an underground reservoir after a fixed period of CO2 injection, while time
Semans, Joseph P. (Uniontown, PA); Johnson, Peter G. (Pittsburgh, PA); LeBoeuf, Jr., Robert F. (Clairton, PA); Kromka, Joseph A. (Idaho Falls, ID); Goron, Ronald H. (Connellsville, PA); Hay, George D. (Venetia, PA)
1993-01-01T23:59:59.000Z
A trainer, mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system.
Semans, J.P.; Johnson, P.G.; LeBoeuf, R.F. Jr.; Kromka, J.A.; Goron, R.H.; Hay, G.D.
1991-04-30T23:59:59.000Z
This invention, a trainer mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system.
hal-00145315,version3-2Aug2007 Viscous potential free-surface flows in a fluid layer of finite depth
Paris-Sud XI, Université de
´equations. Key words: potential flow, free-surface flow, viscosity, dissipation, water waves, wave damping-surface elevation. A new predominant nonlocal viscous term is derived in the bottom kinematic boundary condition potential flow theories [7]. Corresponding long wave model equations are derived. R´esum´e Ecoulements
Miller, Travis Reed
2010-01-01T23:59:59.000Z
This work aimed to inform the design of ceramic pot filters to be manufactured by the organization Pure Home Water (PHW) in Northern Ghana, and to model the flow through an innovative paraboloid-shaped ceramic pot filter. ...
Pfeiffer, Thomas
2011-02-22T23:59:59.000Z
process in the design phase of the project. Assessing reservoir compartment connectivity is of paramount importance for a optimal field development. Recent technological advances in wireline formation testing and sampling provide asset teams with a new...
Compressor bleed cooling fluid feed system
Donahoo, Eric E; Ross, Christopher W
2014-11-25T23:59:59.000Z
A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.
Lopez Hernandez, Henry De Jesus
2004-11-15T23:59:59.000Z
to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 2004 Major Subject: Petroleum Engineering...) _______________________________ Guy L. Curry (Member) _______________________________ Stephen A. Holditch (Head of Department) August 2004 Major Subject: Petroleum Engineering iii ABSTRACT Optimal Fracture Treatment Design for Dry Gas Wells Maximizes...
arXiv:1301.0752v1[physics.flu-dyn]4Jan2013 Fluid-particle flow modelling and validation using
Luding, Stefan
-way-coupled mesoscale SPH-DEM Martin Robinsona, , Stefan Ludinga , Marco Ramaiolib aMultiscale Mechanics, University required to resolve the pore-scale is too great. It then becomes necessary to use unresolved, or mesoscale, fluid simulations. This mesoscale is the focus of this paper and the domain of applicability for the SPH
Gray, Harold E. (Las Vegas, NV); McLaurin, Felder M. (Las Vegas, NV); Ortiz, Monico (Las Vegas, NV); Huth, William A. (Las Vegas, NV)
1996-01-01T23:59:59.000Z
A device or system for monitoring for the presence of leaks from a hazardous fluid is disclosed which uses two electrodes immersed in deionized water. A gas is passed through an enclosed space in which a hazardous fluid is contained. Any fumes, vapors, etc. escaping from the containment of the hazardous fluid in the enclosed space are entrained in the gas passing through the enclosed space and transported to a closed vessel containing deionized water and two electrodes partially immersed in the deionized water. The electrodes are connected in series with a power source and a signal, whereby when a sufficient number of ions enter the water from the gas being bubbled through it (indicative of a leak), the water will begin to conduct, thereby allowing current to flow through the water from one electrode to the other electrode to complete the circuit and activate the signal.
High-potential Working Fluids for Next Generation Binary Cycle Geothermal Power Plants
Broader source: Energy.gov [DOE]
DOE Geothermal Peer Review 2010 - Presentation. Project objective: Find optimized working fluid/advanced cycle combination for EGS applications.
Laser microfluidics : fluid actuation by light Laser microfluidics: fluid actuation by light
Paris-Sud XI, Universit de
Laser microfluidics : fluid actuation by light Laser microfluidics: fluid actuation by light Jean.delville@cpmoh.u-bordeaux1.fr Abstract: The development of microfluidic devices is still hindered by the lack of robust to extend this concept to microfluidic two-phase flows. First, we investigate the destabilization of fluid
Thickness distribution of a cooling pyroclastic flow deposit on Augustine Volcano, Alaska of Volcanology and Geothermal Research 150 (2006) 186201 www.elsevier.com/locate/jvolgeores #12;imagery have al., 2001), poroelastic rebound (Peltzer et al., 1996), cooling lava (Stevens et al., 2001
Amsterdam, Universiteit van
1999-01-01T23:59:59.000Z
1033 (1999) LATTICE-BOLTZMANN AND FINITE ELEMENT SIMULATIONS OF FLUID FLOW IN A SMRX STATIC MIXER REACTOR D-dimensional fluid flow simulations in an SMRX static mixer were performed. The SMRX static mixer is a piece methods. Copyright © 1999 John Wiley & Sons, Ltd. KEY WORDS: static mixer; finite element method; lattice
Microelectromechanical flow control apparatus
Okandan, Murat (NE Albuquerque, NM)
2009-06-02T23:59:59.000Z
A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.
Fluid delivery control system | OSTI, US Dept of Energy, Office...
Office of Scientific and Technical Information (OSTI)
Fluid delivery control system Re-direct Destination: A method of controlling the delivery of fluid to an engine includes receiving a fuel flow rate signal. An electric pump is...
Slow wave in fluid-filled Fractures: What is missing in Biot's theory?
Valeri Korneev, Lawrence Berkeley Nat'l Lab, Berkeley
2007-08-03T23:59:59.000Z
role of fractures in fluid-flow processes at field scales, and ... fluid-filled fractures and an elastic, embedding matrix does not have the .... Non-viscous fluid h.
A refined volume-of-fluid algorithm for capturing sharp fluid interfaces on arbitrary meshes
Zhang, Di; Jiang, Chunbo; Liang, Dongfang; Chen, Zhengbing; Yang, Yan; Shi, Ying
2014-06-30T23:59:59.000Z
conserve mass, and can be easily extended to unstructured meshes and three dimensions, so they are capable of accurately capturing the free surface and modelling merging and fragmentation in multiphase flows. In this article, a new blended high... -tracking method for the computations of multiphase flow. Journal of Computational Physics 2001; 169(2): 708759. 21 14. Harlow FH, Welch JE. Numerical calculation of time-dependent viscous incompressible flow of fluid with free surface. Physics of Fluids...
Castro Gouveia, M. de; Reis Parise, J.A. dos; Nieckele, A.O. (Pontificia Univ. Catolica, Rio de Janeiro (Brazil))
1992-05-01T23:59:59.000Z
A numerical simulation of the scavenging process in a two-stroke flat-piston model engine has been developed. Air enters the cylinder circumferentially, inducting a three-dimensional turbulent swirling flow. The problem was modeled as a steady-state axisymmetric flow through a cylinder with uniform wall temperature. The steady-state regime was simulated by assuming the piston head fixed at the bottom dead center. The calculation was performed employing the {kappa}-{epsilon} model of turbulence. A comparison of the results obtained for the flow field with available experimental data showed very good agreement, and a comparison with an available numerical solution revealed superior results. The effects of the Reynolds number, inlet port angles, and engine geometry on the flow and in-cylinder heat transfer characteristics were investigated. The Nusselt number substantially increases with larger Reynolds numbers and a smaller bore-to-stroke ratio. It is shown that the positioning of the exhaust value(s) is the main parameter to control the scavenging process.
Texas at Austin. University of
motion of the individual molecules in mixing dye to all parts of the system. When this stirring is random rotating tank filled with water to study the random walks of tracer particles in two different flows: one with coherent structures (vortices and jets), and one without (weakly turbulent). Most random walks
Tùma, Miroslav
's law and the continuity equation is solved. Mixedhybrid finite element formulation based on general residual method Rate of convergence Asymptotic convergence factor 1. Introduction The potential flow of polluted groundwater in porous media is usually modelled by a mixed or mixedhybrid formulations which
6. Fluid mechanics: fluid statics; fluid dynamics
Zevenhoven, Ron
Figure Pressure (a scalar!) is defined as surface force / area, for example pb = Fb / (dw) = p @ z = z1 Picture: KJ05 Fluid volume hdw with density and mass m = hdw z = z1 In engineering forces Fn+ Fs = 0 or - pyhw + pyhw = 0 py = 0 Similarly Fw+ Fe= 0 gives px = 0, There are three
Pinkel, Daniel (Walnut Creek, CA)
1991-01-01T23:59:59.000Z
An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.
amniotic fluid index: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Fluid Flows Physics (arXiv) Summary: Dow Jones Index time series exhibit irregular or fractal fluctuations on all time scales from days, months to years. The nonlinear...
ascitic fluid analysis: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to quantify the randomness degree in river flow time series of two mountain rivers in Bosnia and Herzegovina, representing the turbulent environmental fluid, for the period...
Fluid Inclusion Analysis At International Geothermal Area Mexico...
fields; hence fluid-flow plots as presented here can be accomplished with little cost. Gas analytical data, therefore, are useful in developing management procedures for...
Fluid permeability measurement system and method
Hallman, Jr., Russell Louis (Knoxville, TN); Renner, Michael John (Oak Ridge, TN)
2008-02-05T23:59:59.000Z
A system for measuring the permeance of a material. The permeability of the material may also be derived. The system provides a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.
Computational fluid dynamic applications
Chang, S.-L.; Lottes, S. A.; Zhou, C. Q.
2000-04-03T23:59:59.000Z
The rapid advancement of computational capability including speed and memory size has prompted the wide use of computational fluid dynamics (CFD) codes to simulate complex flow systems. CFD simulations are used to study the operating problems encountered in system, to evaluate the impacts of operation/design parameters on the performance of a system, and to investigate novel design concepts. CFD codes are generally developed based on the conservation laws of mass, momentum, and energy that govern the characteristics of a flow. The governing equations are simplified and discretized for a selected computational grid system. Numerical methods are selected to simplify and calculate approximate flow properties. For turbulent, reacting, and multiphase flow systems the complex processes relating to these aspects of the flow, i.e., turbulent diffusion, combustion kinetics, interfacial drag and heat and mass transfer, etc., are described in mathematical models, based on a combination of fundamental physics and empirical data, that are incorporated into the code. CFD simulation has been applied to a large variety of practical and industrial scale flow systems.
Effects of interstitial flow on tumor cell migration
Polacheck, William J. (William Joseph)
2010-01-01T23:59:59.000Z
Interstitial flow is the convective transport of fluid through tissue extracellular matrix. This creeping fluid flow has been shown to affect the morphology and migration of cells such as fibroblasts, cancer cells, endothelial ...
Fluid jet electric discharge source
Bender, Howard A. (Ripon, CA)
2006-04-25T23:59:59.000Z
A fluid jet or filament source and a pair of coaxial high voltage electrodes, in combination, comprise an electrical discharge system to produce radiation and, in particular, EUV radiation. The fluid jet source is composed of at least two serially connected reservoirs, a first reservoir into which a fluid, that can be either a liquid or a gas, can be fed at some pressure higher than atmospheric and a second reservoir maintained at a lower pressure than the first. The fluid is allowed to expand through an aperture into a high vacuum region between a pair of coaxial electrodes. This second expansion produces a narrow well-directed fluid jet whose size is dependent on the size and configuration of the apertures and the pressure used in the reservoir. At some time during the flow of the fluid filament, a high voltage pulse is applied to the electrodes to excite the fluid to form a plasma which provides the desired radiation; the wavelength of the radiation being determined by the composition of the fluid.
Optimization Online - Performance of CONDOR, a Parallel ...
Frank Vanden Berghen
2004-08-19T23:59:59.000Z
Aug 19, 2004 ... ... Fluid Dynamic) codes or PDE (partial differential equations) solvers. ... Keywords: non-linear, lagrange interpolation, optimal shape design,...
Standardization of Thermo-Fluid Modeling in Modelica.Fluid
Franke, Rudiger; Casella, Francesco; Sielemann, Michael; Proelss, Katrin; Otter, Martin; Wetter, Michael
2009-09-01T23:59:59.000Z
This article discusses the Modelica.Fluid library that has been included in the Modelica Standard Library 3.1. Modelica.Fluid provides interfaces and basic components for the device-oriented modeling of onedimensional thermo-fluid flow in networks containing vessels, pipes, fluid machines, valves and fittings. A unique feature of Modelica.Fluid is that the component equations and the media models as well as pressure loss and heat transfer correlations are decoupled from each other. All components are implemented such that they can be used for media from the Modelica.Media library. This means that an incompressible or compressible medium, a single or a multiple substance medium with one or more phases might be used with one and the same model as long as the modeling assumptions made hold. Furthermore, trace substances are supported. Modeling assumptions can be configured globally in an outer System object. This covers in particular the initialization, uni- or bi-directional flow, and dynamic or steady-state formulation of mass, energy, and momentum balance. All assumptions can be locally refined for every component. While Modelica.Fluid contains a reasonable set of component models, the goal of the library is not to provide a comprehensive set of models, but rather to provide interfaces and best practices for the treatment of issues such as connector design and implementation of energy, mass and momentum balances. Applications from various domains are presented.
Optimization Online - Multimaterial topology optimization by volume ...
R Tavakoli
2013-11-14T23:59:59.000Z
Nov 14, 2013 ... The update procedure is based on the gradient flow of the objective functional by a fractional ... descent method, Computer Methods in Applied Mechanics and Engineering, to appear, 2014. ... Mathematical Optimization Society.
Stosic, Zoran V. [Framatome ANP GmbH, PO Box 3220, Erlangen, 91050 (Germany); Stevanovic, Vladimir D. [University of Belgrade, Kraljice Marije 16, 11000 Belgrade, Serbia and Montenegro (Yugoslavia); Tadashi Iguchi [Japan Atomic Energy Research Institute, Tokai-mura 319-1195 (Japan)
2002-07-01T23:59:59.000Z
The investigation of three-dimensional transient propagations of dry-out fronts within a nuclear fuel rod bundle is performed, based on experimental and numerical simulations. The spreading of Critical Heat Flux (CHF) fronts across a bundle, caused by sudden decrease of coolant mass flow rate followed by delayed gradual decrease of power generation is predicted, and the locus of dry patches is shown. Simultaneous occurrence of CHF and re-wet multi-fronts in here-analysed flow transient has not been detected so obvious as in power transient, previously analysed. Due to a possible building of a vapour zone, the CHF front spatial propagation has to be carefully analysed in transient conditions. (authors)
Celik, I.; Chattree, M.
1988-07-01T23:59:59.000Z
An assessment of the theoretical and numerical aspects of the computer code, PCGC-2, is made; and the results of the application of this code to the Morgantown Energy Technology Center (METC) advanced gasification facility entrained-flow reactor, ''the gasifier,'' are presented. PCGC-2 is a code suitable for simulating pulverized coal combustion or gasification under axisymmetric (two-dimensional) flow conditions. The governing equations for the gas and particulate phase have been reviewed. The numerical procedure and the related programming difficulties have been elucidated. A single-particle model similar to the one used in PCGC-2 has been developed, programmed, and applied to some simple situations in order to gain insight to the physics of coal particle heat-up, devolatilization, and char oxidation processes. PCGC-2 was applied to the METC entrained-flow gasifier to study numerically the flash pyrolysis of coal, and gasification of coal with steam or carbon dioxide. The results from the simulations are compared with measurements. The gas and particle residence times, particle temperature, and mass component history were also calculated and the results were analyzed. The results provide useful information for understanding the fundamentals of coal gasification and for assessment of experimental results performed using the reactor considered. 69 refs., 35 figs., 23 tabs.
Oscillating fluid power generator
Morris, David C
2014-02-25T23:59:59.000Z
A system and method for harvesting the kinetic energy of a fluid flow for power generation with a vertically oriented, aerodynamic wing structure comprising one or more airfoil elements pivotably attached to a mast. When activated by the moving fluid stream, the wing structure oscillates back and forth, generating lift first in one direction then in the opposite direction. This oscillating movement is converted to unidirectional rotational movement in order to provide motive power to an electricity generator. Unlike other oscillating devices, this device is designed to harvest the maximum aerodynamic lift forces available for a given oscillation cycle. Because the system is not subjected to the same intense forces and stresses as turbine systems, it can be constructed less expensively, reducing the cost of electricity generation. The system can be grouped in more compact clusters, be less evident in the landscape, and present reduced risk to avian species.
Dr. Chenn Zhou
2008-10-15T23:59:59.000Z
Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process.
Diffusion driven object propulsion in density stratified fluids
Lenahan, Conor (Conor P.)
2009-01-01T23:59:59.000Z
An experimental study was conducted in order to verify the appropriateness of a two dimensional model of the flow creating diffusion driven object propulsion in density stratified fluids. Initial flow field experiments ...
Locomotion in complex fluids: Integral theorems
Eric Lauga
2014-10-15T23:59:59.000Z
The biological fluids encountered by self-propelled cells display complex microstructures and rheology. We consider here the general problem of low-Reynolds number locomotion in a complex fluid. {Building on classical work on the transport of particles in viscoelastic fluids,} we demonstrate how to mathematically derive three integral theorems relating the arbitrary motion of an isolated organism to its swimming kinematics {in a non-Newtonian fluid}. These theorems correspond to three situations of interest, namely (1) squirming motion in a linear viscoelastic fluid, (2) arbitrary surface deformation in a weakly non-Newtonian fluid, and (3) small-amplitude deformation in an arbitrarily non-Newtonian fluid. Our final results, valid for a wide-class of {swimmer geometry,} surface kinematics and constitutive models, at most require mathematical knowledge of a series of Newtonian flow problems, and will be useful to quantity the locomotion of biological and synthetic swimmers in complex environments.
Simulating Fluids Exhibiting Microstructure
Title: Simulating Fluids Exhibiting Microstructure Speaker: Noel J. Walkington, ... fluids containing elastic particles, and polymer fluids, all exhibit non-trivial...
Fuel cell membrane hydration and fluid metering
Jones, Daniel O. (Glenville, NY); Walsh, Michael M. (Fairfield, CT)
2003-01-01T23:59:59.000Z
A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).
Fuel cell membrane hydration and fluid metering
Jones, Daniel O. (Glenville, NY); Walsh, Michael M. (Fairfield, CT)
1999-01-01T23:59:59.000Z
A hydration system includes fuel cell fluid flow plate(s) and injection port(s). Each plate has flow channel(s) with respective inlet(s) for receiving respective portion(s) of a given stream of reactant fluid for a fuel cell. Each injection port injects a portion of liquid water directly into its respective flow channel in order to mix its respective portion of liquid water with the corresponding portion of the stream. This serves to hydrate at least corresponding part(s) of a given membrane of the corresponding fuel cell(s). The hydration system may be augmented by a metering system including flow regulator(s). Each flow regulator meters an injecting at inlet(s) of each plate of respective portions of liquid into respective portion(s) of a given stream of fluid by corresponding injection port(s).
Optimization Online - All Areas Submissions - October 2014
Inexactness of SDP Relaxation for Optimal Power Flow over Radial Networks and Valid ... Optimization Software and Modeling Systems ... Semi-definite relaxations for optimal control problems with oscillation and concentration effects
ME 330001 INTRODUCTION TO FLUID MECHANICS Fall 2004 MWF 8:008:50 AM, RGAN 202
McDonough, James M.
& Lagrangian descriptions of flow Turbulent pipe flow Substantial derivative Moody chart Gauss & general pipe flows. 6. Use the energy equation to predict pressure drop in pipes, across fittings and through. Course Description: Physical properties of fluids and classification of fluid flows. Integral
Boundary Integral Methods for Multicomponent Fluids and Multiphase Materials
integral methods in two dimensions to multi-component fluid flows and multi-phase problems in materials, and more recently to multi-phase problems in materials science. By multi-fluid or multi-phase we mean systems where the constituitive properties of the fluid or material change abruptly at a dividing
Boundary Integral Methods for Multicomponent Fluids and Multiphase Materials
integral methods in two dimensions to multicomponent fluid flows and multiphase problems in materials, and more recently to multiphase problems in materials science. By multifluid or multiphase we mean systems where the constituitive properties of the fluid or material change abruptly at a dividing
Caughey, David
2010-10-08T23:59:59.000Z
A Symposium on Turbulence and Combustion was held at Cornell University on August 3-4, 2009. The overall goal of the Symposium was to promote future advances in the study of turbulence and combustion, through an unique forum intended to foster interactions between leading members of these two research communities. The Symposium program consisted of twelve invited lectures given by world-class experts in these fields, two poster sessions consisting of nearly 50 presentations, an open forum, and other informal activities designed to foster discussion. Topics covered in the lectures included turbulent dispersion, wall-bounded flows, mixing, finite-rate chemistry, and others, using experiment, modeling, and computations, and included perspectives from an international community of leading researchers from academia, national laboratories, and industry.
2005 Pearson Education South Asia Pte Ltd Applied Fluid Mechanics
Leu, Tzong-Shyng "Jeremy"
Education South Asia Pte Ltd Applied Fluid Mechanics 17.Drag and Lift 18.Fans, Blowers, Compressors-Momentum Equation 4. Problem-Solving Method Using the Force Equations 5. Forces on Stationary Objects 6. Forces Pearson Education South Asia Pte Ltd 16.2 Force Equation In fluid flow problems, a continuous flow
Fluid forces on two circular cylinders in crossflow
Jendrzejczyk, J.A.; Chen, S.S.
1986-01-01T23:59:59.000Z
Fluid excitation forces are measured in a water loop for two circular cylinders arranged in tandem and normal to flow. The Strouhal number and fluctuating drag and lift coefficients for both cylinders are presented for various spacings and incoming flow conditions. The results show the effects of Reynolds number, pitch ratio, and upstream turbulence on the fluid excitation forces.
Wai, Chien M. (Moscow, ID); Laintz, Kenneth E. (Los Alamos, NM)
1999-01-01T23:59:59.000Z
A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The method is particularly useful for extracting actinides and lanthanides from acidic solutions. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.
Pressure balanced drag turbine mass flow meter
Dacus, Michael W. (Gilbert, AR); Cole, Jack H. (Fayetteville, AR)
1982-01-01T23:59:59.000Z
The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.
Pressure balanced drag turbine mass flow meter
Dacus, M.W.; Cole, J.H.
1980-04-23T23:59:59.000Z
The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.
McEligot, D.M.; Condie, K.G.; Foust, T.D.; McCreery, G.E.; Pink, R.J.; Stacey, D.E. (INEEL); Shenoy, A.; Baccaglini, G. (General Atomics); Pletcher, R.H. (Iowa State U.); Wallace, J.M.; Vukoslavcevic, P. (U. Maryland); Jackson, J.D. (U. Manchester, UK); Kunugi, T. (Kyoto U., Japan); Satake, S.-i. (Tokyo U. Science, Japan)
2002-12-31T23:59:59.000Z
The ultimate goal of the study is the improvement of predictive methods for safety analyses and design of advanced reactors for higher efficiency and enhanced safety and for deployable reactors for electrical power generation, process heat utilization and hydrogen generation. While key applications would be advanced gas-cooled reactors (AGCRs) using the closed Brayton cycle (CBC) for higher efficiency (such as the proposed Gas Turbine - Modular Helium Reactor (GT-MHR) of General Atomics [Neylan and Simon, 1996]), results of the proposed research should also be valuable in reactor systems with supercritical flow or superheated vapors, e.g., steam. Higher efficiency leads to lower cost/kwh and reduces life-cycle impacts of radioactive waste (by reducing waters/kwh). The outcome will also be useful for some space power and propulsion concepts and for some fusion reactor concepts as side benefits, but they are not the thrusts of the investigation. The objective of the project is to provide fundamental thermal fluid physics knowledge and measurements necessary for the development of the improved methods for the applications.
Paris-Sud XI, Universit de
: 43.25.Qp, 42.50.Wk. When the bottom fluid is pumped through a tube above a horizontal interface by the action of bulk flows driven by a laser beam. These streaming flows are due to light scattering losses separating two immiscible fluids, the upper fluid is withdrawn and a jet occurs above a threshold flow rate
High speed flow cytometer droplet formation system and method
Van den Engh, Ger (Seattle, WA)
2000-01-01T23:59:59.000Z
A droplet forming flow cytometer system allows high speed processing without the need for high oscillator drive powers through the inclusion of an oscillator or piezoelectric crystal such as within the nozzle volume or otherwise unidirectionally coupled to the sheath fluid. The nozzle container continuously converges so as to amplify unidirectional oscillations which are transmitted as pressure waves through the nozzle volume to the nozzle exit so as to form droplets from the fluid jet. The oscillator is directionally isolated so as to avoid moving the entire nozzle container so as to create only pressure waves within the sheath fluid. A variation in substance concentration is achieved through a movable substance introduction port which is positioned within a convergence zone to vary the relative concentration of substance to sheath fluid while still maintaining optimal laminar flow conditions. This variation may be automatically controlled through a sensor and controller configuration. A replaceable tip design is also provided whereby the ceramic nozzle tip is positioned within an edge insert in the nozzle body so as to smoothly transition from nozzle body to nozzle tip. The nozzle tip is sealed against its outer surface to the nozzle body so it may be removable for cleaning or replacement.
Awwad, Ghassan Samir
2009-01-01T23:59:59.000Z
Selecting and executing the optimal strategy for developing new products is a non trivial task, especially for low volume, high complexity products in a highly volatile global industry such as Fluid Management. At Fluid ...
VanOsdol, John G.
2013-06-25T23:59:59.000Z
The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.
Controlled differential pressure system for an enhanced fluid blending apparatus
Hallman, Jr., Russell Louis (Knoxville, TN)
2009-02-24T23:59:59.000Z
A system and method for producing a controlled blend of two or more fluids. Thermally-induced permeation through a permeable tube is used to mix a first fluid from outside the tube with a second fluid flowing through the tube. Mixture ratios may be controlled by adjusting the temperature of the first fluid or by adjusting the pressure drop through the permeable tube. The combination of a back pressure control valve and a differential regulator is used to control the output pressure of the blended fluid. The combination of the back pressure control valve and differential regulator provides superior flow control of the second dry gas. A valve manifold system may be used to mix multiple fluids, and to adjust the volume of blended fluid produced, and to further modify the mixture ratio.
Design optimization of oxygenated fluid pump
Piazzarolo, Bruno Aiala
2012-01-01T23:59:59.000Z
In medical emergencies, an oxygen-starved brain quickly suffers irreparable damage. In many cases, patients who stop breathing can be resuscitated but suffer from brain damage. Dr. John Kheir from Boston Children's Hospital ...
Fluid Dynamics in Sucker Rod Pumps
Cutler, R.P.; Mansure, A.J.
1999-01-14T23:59:59.000Z
Sucker rod pumps are installed in approximately 90% of all oil wells in the U.S. Although they have been widely used for decades, there are many issues regarding the fluid dynamics of the pump that have not been fully investigated. A project was conducted at Sandia National Laboratories to develop unimproved understanding of the fluid dynamics inside a sucker rod pump. A mathematical flow model was developed to predict pressures in any pump component or an entire pump under single-phase fluid and pumping conditions. Laboratory flow tests were conducted on instrumented individual pump components and on a complete pump to verify and refine the model. The mathematical model was then converted to a Visual Basic program to allow easy input of fluid, geometry and pump parameters and to generate output plots. Examples of issues affecting pump performance investigated with the model include the effects of viscosity, surface roughness, valve design details, plunger and valve pressure differentials, and pumping rate.
Raffray, A. Ren
2014-01-01T23:59:59.000Z
analysis for cooling the ITER Blanket System, Fusion Eng. Des. (2014), http://dx.doi.org/10.1016/j.elsevier.com/locate/fusengdes Optimized mass flow rate distribution analysis for cooling the ITER Blanket System Germn Prez , Raphal: ITER Blanket System Mass flow rate Critical heat flux a b s t r a c t This paper presents the rationale
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Dilley, Lorie
Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.
Dilley, Lorie
2013-01-01T23:59:59.000Z
Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.
Fuel cell system with coolant flow reversal
Kothmann, Richard E. (Pittsburgh, PA)
1986-01-01T23:59:59.000Z
Method and apparatus for cooling electrochemical fuel cell system components. Periodic reversal of the direction of flow of cooling fluid through a fuel cell stack provides greater uniformity and cell operational temperatures. Flow direction through a recirculating coolant fluid circuit is reversed through a two position valve, without requiring modulation of the pumping component.
Murray's law revisited with Qu\\'emada's fluids and fractal trees
Benjamin, Mauroy
2015-01-01T23:59:59.000Z
In 1926, Murray proposed the first law for the optimal design of blood vessels. He minimized the power dissipation arising from the trade-off between fluid circulation and blood maintenance. The law, based on a constant fluid viscosity, states that in the optimal configuration the fluid flow rate inside the vessel is proportional to the cube of the vessel radius, implying that wall shear stress is not dependent on the vessel radius. Murray's law has been found to be true in blood macrocirculation, but not in microcirculation. In 2005, Alarc\\'on et al took into account the non monotonous dependence of viscosity on vessel radius - F{\\aa}hr{\\ae}us - Lindqvist effect - due to phase separation effect of blood. They were able to predict correctly the behavior of wall shear stresses in microcirculation. One last crucial step remains however: to account for the dependence of blood viscosity on shear rates. In this work, we investigate how viscosity dependence on shear rate affects Murray's law. We extended Murray's o...
Control system for fluid heated steam generator
Boland, James F. (Bonneville County, ID); Koenig, John F. (Idaho Falls, ID)
1985-01-01T23:59:59.000Z
A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.
Control system for fluid heated steam generator
Boland, J.F.; Koenig, J.F.
1984-05-29T23:59:59.000Z
A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.
Smart Grid Application of Optimal Transmission Switching
Ferris, Michael C.
;6 Introduction continued Electric Transmission Network Flow Problem Optimal Power Flow (OPF) AlternatingSmart Grid Application of Optimal Transmission Switching By, Kory W. Hedman, et al.* University (Professor, UC Berkeley) #12;2 Motivation Co-optimize transmission topology and generation dispatch
Thermo-Fluids, Energy Systems and Environment This group conducts research in the following areas
Calgary, University of
and Reacting Flows l Aerodynamics l Internal-Combustion Engines l Stirling Engines l Computational Fluid internal-combustion engines l Cross-flow and co-flow combustion facilities l Flammability test apparatus l-Fluids, Energy Systems and Environment This group conducts research in the following areas: l Combustion
Interface instabilities during displacements of two miscible fluids in a vertical pipe
Lajeunesse, Eric
superposed layers of fluids of different viscosities between two horizontal plates. He showed that the flow analysis of steady concentric flow of two fluids in a vertical circular tube. He considered both asymmetric for diffusive effects to be negligible. For certain viscosity ratios and flow rates, the interface between
Structural optimization of the Ziegler's pendulum: singularities and ...
2010-12-24T23:59:59.000Z
Dec 24, 2010 ... Structural optimization of non-conservative systems with respect to ... criteria is a research area with important applications in fluid-structure in-.
Theory of locomotion through complex fluids
Gwynn Elfring; Eric Lauga
2014-10-16T23:59:59.000Z
Microorganisms such as bacteria often swim in fluid environments that cannot be classified as Newtonian. Many biological fluids contain polymers or other heterogeneities which may yield complex rheology. For a given set of boundary conditions on a moving organism, flows can be substantially different in complex fluids, while non-Newtonian stresses can alter the gait of the microorganisms themselves. Heterogeneities in the fluid may also be characterized by length scales on the order of the organism itself leading to additional dynamic complexity. In this chapter we present a theoretical overview of small-scale locomotion in complex fluids with a focus on recent efforts quantifying the impact of non-Newtonian rheology on swimming microorganisms.
Pumping viscoelastic two-fluid media
Hirofumi Wada
2010-04-08T23:59:59.000Z
Using a two-fluid model for viscoelastic polymer solutions, we study analytically fluid transport driven by a transverse, small amplitude traveling wave propagation. The pumping flow far from the waving boundary is shown to be strongly wave number and viscosity dependent, in contrast to a viscous Newtonian fluid. We find the two qualitatively different regimes: In one regime relevant to small wave numbers, the fluidic transport is almost the same as the Newtonian case, and uniform viscoelastic constitutive equations provide a good approximation. In the other regime, the pumping is substantially decreased because of the gel-like character. The boundary separating these two regimes is clarified. Our results suggest possible needs of two-fluid descriptions for the transport and locomotion in biological fluids with cilia and flagella.
2005 Pearson Education South Asia Pte Ltd Applied Fluid Mechanics
Leu, Tzong-Shyng "Jeremy"
loss due to friction in laminar flow. Define the friction factor as used in Darcy's equation. Critical Reynolds Numbers 4. Darcy's Equation 5. Friction Loss in Laminar Flow 6. Friction Loss. Buoyancy and Stability 6. Flow of Fluid and Bernoulli's Equation 7. General Energy Equation 8. Reynolds
Methods of conveying fluids and methods of sublimating solid particles
Turner, Terry D; Wilding, Bruce M
2013-10-01T23:59:59.000Z
A heat exchanger and associated methods for sublimating solid particles therein, for conveying fluids therethrough, or both. The heat exchanger includes a chamber and a porous member having a porous wall having pores in communication with the chamber and with an interior of the porous member. A first fluid is conveyed into the porous member while a second fluid is conveyed into the porous member through the porous wall. The second fluid may form a positive flow boundary layer along the porous wall to reduce or eliminate substantial contact between the first fluid and the interior of the porous wall. The combined first and second fluids are conveyed out of the porous member. Additionally, the first fluid and the second fluid may each be conveyed into the porous member at different temperatures and may exit the porous member at substantially the same temperature.
System and method for improving performance of a fluid sensor for an internal combustion engine
Kubinski, David (Canton, MI); Zawacki, Garry (Livonia, MI)
2009-03-03T23:59:59.000Z
A system and method for improving sensor performance of an on-board vehicle sensor, such as an exhaust gas sensor, while sensing a predetermined substance in a fluid flowing through a pipe include a structure for extending into the pipe and having at least one inlet for receiving fluid flowing through the pipe and at least one outlet generally opposite the at least one inlet, wherein the structure redirects substantially all fluid flowing from the at least one inlet to the sensor to provide a representative sample of the fluid to the sensor before returning the fluid through the at least one outlet.
Influence and optimization of the electrodes position in a piezoelectric energy harvesting flag
Pieirua, Miguel; Michelin, Sbastien
2015-01-01T23:59:59.000Z
Fluttering piezoelectric plates may harvest energy from a fluid flow by converting the plate's mechanical deformation into electric energy in an output circuit. This work focuses on the influence of the arrangement of the piezoelectric electrodes along the plate's surface on the energy harvesting efficiency of the system, using a combination of experiments and numerical simulations. A weakly non-linear model of a plate in axial flow, equipped with a discrete number of piezoelectric patches is derived and confronted to experimental results. Numerical simulations are then used to optimize the position and dimensions of the piezoelectric electrodes. These optimal configurations can be understood physically in the limit of small and large electromechanical coupling.
Viscous exchange flows Gary P. Matson and Andrew J. Hogg
Hogg, Andrew
-based expressions for the gas mass flow rate and pressure profile in a microscale tube Phys. Fluids 24, 012005 (2012 viscosities, counter-flow within a horizontal channel, are found in many industrial and environmental settingsViscous exchange flows Gary P. Matson and Andrew J. Hogg Citation: Phys. Fluids 24, 023102 (2012